# DTP 3-way valve.....?



## joey24dirt (Jan 28, 2017)

Right then this has been on my mind for a while now and I'm wondering if it's at all possible to do this. I want to install a 3-way valve onto my DTP just to see if it will actually work.

There's plenty of space inside the machine but I'm just curious as to the actual arrangement and placement of the valve. Do they need their own separate port on the brew head or could it potentially be 'T'ed in on the line feeding the brew head?

Here's a picture of the port going in. It's supplied by 4mm OD plastic pipe










Just after having a quick look I've noticed something that may be a life saver for this whole project.










Where the screwdriver is aimed there's a screw that looks like it could be a port blank for the brew head. Maybe a universal head that some sage have a valve installed and some don't. Fingers crossed it is what I think it is.

Further digging required...


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## joey24dirt (Jan 28, 2017)

Yup it's a blank for a small port hole into the brew head. This could potentially be used to install a 3-way valve. I'd have to drill and tap the housing though which is a scary prospect


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## khampal (Feb 6, 2017)

Just a thought: I think the Breville Infuser (a DTP with more features basically) has a 3 way valve, and I imagine they would have a lot in common internally. If you can see where it fits into the Infuser then maybe the same would apply to the DTP? You may even be able to purchase spare infuser parts from the US that would fit.


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## khampal (Feb 6, 2017)

Additionally, this may be of interest. Page B and parts 143 to 153 seem to be relevant.

Edit: Clearer diagram of the infuser here

Also it would appear the Barista Express may have similar internals (on the brew side of things) and also has a 3 way valve. See a video of the internals





, might be of use?


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## joey24dirt (Jan 28, 2017)

khampal said:


> Just a thought: I think the Breville Infuser (a DTP with more features basically) has a 3 way valve, and I imagine they would have a lot in common internally. If you can see where it fits into the Infuser then maybe the same would apply to the DTP? You may even be able to purchase spare infuser parts from the US that would fit.


Thanks for the links. I think I'll have to do some more research to see how it exactly all fits together. The thing that would need some good thought is the wiring, and how best to wire it in.


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## DaveP (Jul 14, 2017)

Basically... a '3' way valve does not need to be 3 way, lol

its purpose is to relieve pressure by either allowing pressure to the head or dump it.

There are a few different methods of achieving this, but very basically a NO valve wired to the pump, and Tee'ed into the water feed then dumped into the tray with a bit of pipe.

Normal caveats apply to prevent syphoning.

I have a 1/8 BSP NO 2 way valve on the slow boat from China for this very purpose









Also have a gaggia 3 way but needs the manifold drilling / taping for conversion so that's on hold until the better plan of using the 2 way has been proven.

Maybe your blanked off port is ideal and ready made for the 2 way purpose, whats the size ?


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## kennyboy993 (Jan 23, 2017)

Looks an interesting project Joey - just out of interest could you explain what new capability this would give your DTP? I sort of understand what a 3-way does though understanding more about the outcome of the whole machine would be very interesting


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## joey24dirt (Jan 28, 2017)

Just to try get rid of some of the excess pressure/water once the shot has been pulled. To be honest, I know it's not a necessity but I just can't help tinkering about lol. Hopefully I don't end up screwing my machine up


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## longhardgrind (Mar 17, 2017)

Isn't a three way valve a prerequisite for proper backflushing, which a DTP can't actually manage?


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## joey24dirt (Jan 28, 2017)

Well I did think about this. To be honest I'm just going to use this as a bit of an experiment to see if will dry the puck a bit more than it does currently. All the mods I'll be doing can be easily removed if I need them to be.

With regards to back flushing I'm hoping that with the configuration I'll go for it will perform some kind of back flush when I run the cleaning tabs. If it doesn't then it's no great issue getting into this machine and manually cleaning everything. I'm using 6mm push fit connections so it will strip easily at least..... I hope


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## DaveP (Jul 14, 2017)

> Isn't a three way valve a prerequisite for proper backflushing


Indeed so, which is why care has to be taken in deciding where in the water flow scheme of things the valve is placed, as back flushing could have

a nasty tasting consequence, lol


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## longhardgrind (Mar 17, 2017)

My puck dryness varies quite a lot, I generally put it down to having good and bad days, because they can change quite a bit within a couple of hours, even though nothing else has changed. So I'll be watching your modification with interest.


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Indeed so, which is why care has to be taken in deciding where in the water flow scheme of things the valve is placed, as back flushing could have
> 
> a nasty tasting consequence, lol


Haha yes. I'm basically using a spare port on the group head so a sharp open and close of the valve should drain it off direct into the drip tray without disturbing anything else. The main feeds for the water into the head will be left well alone.


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## joey24dirt (Jan 28, 2017)

longhardgrind said:


> My puck dryness varies quite a lot, I generally put it down to having good and bad days, because they can change quite a bit within a couple of hours, even though nothing else has changed. So I'll be watching your modification with interest.


My pucks used to be dry with my sage grinder but since switching to the mazzer they are pretty wet. Great coffee though


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## joey24dirt (Jan 28, 2017)

Parts for the mod. 6mm push fits, 2-way solenoid valve and 30 metres of plastic pipe. I literally need less than 500mm but it's sold in full rolls only


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## DaveP (Jul 14, 2017)

I trust thats a NO (normally open.. energise to close) valve ?


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## DaveP (Jul 14, 2017)

O'h and PS.. http://www.ebay.co.uk/itm/PTFE-Teflon-Tubing-Pipe-6mm-od-x-4mm-id-per-metre-free-delivery/110980480615?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

I got a meter from them, dear way to get a meter but cheaper than a roll, lol


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## joey24dirt (Jan 28, 2017)

DaveP said:


> I trust thats a NO (normally open.. energise to close) valve ?


It's a normally closed. It should still work I'll just need to wire it to be open when in standby and then close when pulling a shot. Fingers crossed


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## DaveP (Jul 14, 2017)

> I'll just need to wire it to be open when in standby


Indeed you can make it work .... but it will mean the coil will be in an energized state for prolonged periods (that's only if you don't switch the machine off between uses, lol)

Still, on a good note... the extra 6w of power may help the cup warmer


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Indeed you can make it work .... but it will mean the coil will be in an energized state for prolonged periods (that's only if you don't switch the machine off between uses, lol)
> 
> Still, on a good note... the extra 6w of power may help the cup warmer


Haha yeah more than likely. It should in theory only be in for as long as the machine which is 10-15 mins at a time. I'll see how it goes and if it doesn't work out or fails quick then I'll switch it to a NO type. In truth I ordered the wrong part so I'm making it work however I can. £30 that little sod was


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## joey24dirt (Jan 28, 2017)

Before and after of the modified port. No going back now 



















The port was originally an M4 thread I think. The smallest fitting I could get was an M5 so drilled out and tapped fresh threads into the brew head. Scary prospect....

I wish I'd picked up a few blanks from the suppliers now so I can resume tomorrow evening. I'll have to crack on a bit if I want coffee in the morning


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## joel.stockel (Apr 19, 2017)

joey24dirt said:


> Right then this has been on my mind for a while now and I'm wondering if it's at all possible to do this. I want to install a 3-way valve onto my DTP just to see if it will actually work.
> 
> There's plenty of space inside the machine but I'm just curious as to the actual arrangement and placement of the valve. Do they need their own separate port on the brew head or could it potentially be 'T'ed in on the line feeding the brew head?
> 
> ...


ddddde

Skickat från min SM-G389F via Tapatalk


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## joey24dirt (Jan 28, 2017)

I think I'm going to have to accept defeat with regards to my N/C valve I'm trying to use. Looking at the wiring last night it's going to be way too difficult to figure out, especially when a N/O will be super simple to do.

I could of course install an additional switch to operate the valve but I don't want to have another button to press when it needs to be an automatic thing.

Looks like I'm forking out another £30 for a valve.......

.....anyone in the market for a N/C solenoid valve


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## DaveP (Jul 14, 2017)

To save the day.. you could add a 'change over' relay.


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## joey24dirt (Jan 28, 2017)

DaveP said:


> To save the day.. you could add a 'change over' relay.


Oh wow this is great info. I love this forum. So they literally just switch things around? I wonder if the sparks at work have any kicking about  thanks matey


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## DaveP (Jul 14, 2017)

If you manage to find one, I can draw the connections on the back of a beer mat for you......

However a N.O would of been nice (but you know that, lol)

Heres the one I got (took 16 days to arrive)

http://www.ebay.co.uk/itm/220V-AC-G1-8-N-O-Brass-Electric-Solenoid-Valve-Water-Gas-Air-Normally-Open-Type/172482875647?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649


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## joey24dirt (Jan 28, 2017)

DaveP said:


> If you manage to find one, I can draw the connections on the back of a beer mat for you......
> 
> However a N.O would of been nice (but you know that, lol)
> 
> ...


I can potentially get one today. Just need to catch some of our electricians. Or if it's a chew I'll just order a new valve. I can have one in a couple of days from that solenoid valves uk site.

I'm guessing you've done a mod yourself? I did the same thing on my old delonghi but had a crude set up with a switch and it was all kinds of wrong haha


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## DaveP (Jul 14, 2017)

> I'm guessing you've done a mod yourself?


Good guess ...

Using the relay to change it over does need a tad of out of the box thought, but I have every confidence in you (not in the electricians though)


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Good guess ...
> 
> Using the relay to change it over does need a tad of out of the box thought, but I have every confidence in you (not in the electricians though)


What machine did you mod? Haha thanks for your vote of confidence. I think for ease I'll take the £30 hit


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## DaveP (Jul 14, 2017)

Stand your ground ... a simple mains voltage spdt relay will be all you need and as time is not of the essence it will save you ££ whilst your waiting for a valve from China (and will work just fine for the proof of the pudding)


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Stand your ground ... a simple mains voltage spdt relay will be all you need and as time is not of the essence it will save you ££ whilst your waiting for a valve from China (and will work just fine for the proof of the pudding)


Do you have a link there for the relay then I can match it up in the suppliers when I go


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## DaveP (Jul 14, 2017)

This ... http://www.ebay.co.uk/itm/Finder-40-31-8-240-0000-240V-Relay-Miniature-SPDT-DC-10A-/122327367093?hash=item1c7b477db5:g:Ze0AAOSw4DJYigoY


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## DaveP (Jul 14, 2017)

Here is how I'd connect it....

With sincere apologies if I have mislabeled anything, lol

I have no idea how the connections will be marked on the relay, but a few moments with a multi meter will work it out


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## Rakesh (Jun 3, 2017)

Really looking forward to how you get on with this.


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## joey24dirt (Jan 28, 2017)

Rakesh said:


> Really looking forward to how you get on with this.


I've ordered the relay so that should be here Friday. Had some great advice so far so hopefully it will go well.

If it works are you tempted @Rakesh? I could supply a kit for you haha  I've got 30 metres of this bloody 6mm pipe so there's plenty to go around


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## Rakesh (Jun 3, 2017)

joey24dirt said:


> I've ordered the relay so that should be here Friday. Had some great advice so far so hopefully it will go well.
> 
> If it works are you tempted @Rakesh? I could supply a kit for you haha  I've got 30 metres of this bloody 6mm pipe so there's plenty to go around


So long as it doesn't require intensive diy I'm up for it, I must admit I have no idea what some of you and the other members are talking about re the valve, sounds very complicated to me


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## joey24dirt (Jan 28, 2017)

Rakesh said:


> So long as it doesn't require intensive diy I'm up for it, I must admit I have no idea what some of you and the other members are talking about re the valve, sounds very complicated to me


Search solenoid valve and it should give you a bit of an idea. Just like operating a door with an electric basically


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## joey24dirt (Jan 28, 2017)

Had a couple of hours spare at work this afternoon after getting my jobs done. Strangely enough I had been installing some 3/4" solenoid valves! Way bigger than my 1/8" compact one.

I got the new plumbing installed for the steam vent and configured it so both that and the 3-way (it's actually 2-way) went into the same pipe work and into the drip tray



















This push fit stuff is a breeze to work with for those who might not have much experience with it. The hardest job so far has been trying to secure everything on the inside. I may have to resort to small amounts of silicone.

I haven't done a leak check yet as I'd ran out of time so will hopefully get to so that in the next hour (once kids are asleep)

The flip-flop relay should arrive tomorrow so I can then get that wired in and finally see if all this effort has been worth it haha.

Tbc.........


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## DaveP (Jul 14, 2017)

You have no idea how much it pleases me to see that there is some one else in the whole wide world that can cut a tube with out it looking like an overflow spout.... hahahahahaha


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## Dylan (Dec 5, 2011)

But it is an overflow spout!


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## DaveP (Jul 14, 2017)

Dylan said:


> But it is an overflow spout!


Groan...


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## joey24dirt (Jan 28, 2017)

It's a pretty nice cut haha. The joys of having the right tool for the job I suppose. I still haven't figured out this wiring though @DaveP. I had another look at the diagram and I think I understand what will happen


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## DaveP (Jul 14, 2017)

Its kinda like this...

When the coil does not have any voltage to it, (cos its connected to the brew switch and the brew switch is off)

then the contacts inside the relay are connecting 1 to 2 and thus allowing voltage to the valve (making it be open)

When the coil does have voltage to it (cos the brew switch is on) then

the contacts inside the relay disconnects 1 to 2 and as there is now no voltage going to the valve, it closes.


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Its kinda like this...
> 
> When the coil does not have any voltage to it, (cos its connected to the brew switch and the brew switch is off)
> 
> ...


Got it. Thanks for that. I think the contacts are pins so not sure whether to solder onto them and heat shrink over or get some proper terminals that will fit.


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## DaveP (Jul 14, 2017)

> so not sure whether to solder onto them and heat shrink over or get some proper terminals that will fit.


Either method will be fine


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## joey24dirt (Jan 28, 2017)

It's here @DaveP. Definitely have to solder onto the terminals. Our sparks didn't have anything small enough to connect on


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## DaveP (Jul 14, 2017)

Yes, I forgot that its 'pcb' sized, so solder and heat shrink is the way.

It looks like the center pin of the group of 3 is number 2 on the diagram, and the left pin of the group of 3 is number 1....


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Yes, I forgot that its 'pcb' sized, so solder and heat shrink is the way.
> 
> It looks like the center pin of the group of 3 is number 2 on the diagram, and the left pin of the group of 3 is number 1....


Thanks for the info. Current situation is tesco shopping all over the floor. Baby asleep on my back. Toddler going mental in the front room and I'm on call all weekend so I'm not sure much will get done on the coffee machine


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## joey24dirt (Jan 28, 2017)

Well after a mental weekend of call outs at work I've finally got myself an hour or so before bed to continue with this mod. Seemingly with the replacement exit spout I've installed I've pretty much fixed the issue with water getting all over the hidden compartment. It even sounds different when it vents off as if it's concentrated more into the drip tray as opposed to spraying everywhere. It could also be the fact it's hitting a t-piece before the tray so might be slowing down the initial gush.

Anyway back to the mod. I'm still on call until 7am so fingers crossed nothing comes in haha


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## DaveP (Jul 14, 2017)

Plumbing is easily sorted.... but I take it that the electrical mod part worked ok ?


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Plumbing is easily sorted.... but I take it that the electrical mod part worked ok ?


Just about to start that side of things


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## Rakesh (Jun 3, 2017)

joey24dirt said:


> Just about to start that side of things


Keep us all updated!


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## joey24dirt (Jan 28, 2017)

Wires soldered


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## joey24dirt (Jan 28, 2017)

@DaveP on your drawing can L2 and pin 1 pick up the same live?

Edit... no they can't L2 has to be on the brew switch side for it to work. Answered my own question.... I think


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## DaveP (Jul 14, 2017)

Not as such ....

L1 is a permanent live (comes on with the machine)

L2 needs to be present only when the pump is active (so can be taken from the pump)

Pin 1 on the drawing is directly connected to the valve and is switched by the relay (to L1)


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Not as such ....
> 
> L1 is a permanent live (comes on with the machine)
> 
> ...


The switched live I'm trying to get on is only giving me 70volts. Looks like it goes through a diode before turning the pump on.....

I think it's time for bed haha


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## DaveP (Jul 14, 2017)

Ahhhhhhhhhhhh .... Wondering if the DTP pump AC voltage is ramped up slowly to increase pressure over time (like a dimer switch mod... but with out the dimmer switch, lol) or that is the maximum the pump ever gets to.

Soooooooooo ... the big switch that switches on to 'brew' is there full voltage there or is that at the lower voltage as well ?

If the pump or even the switch cant be used to suit the cunning plan, then there is another way around the problem, that can utilize the lower pump voltage.


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Ahhhhhhhhhhhh .... Wondering if the DTP pump AC voltage is ramped up slowly to increase pressure over time (like a dimer switch mod... but with out the dimmer switch, lol) or that is the maximum the pump ever gets to.
> 
> Soooooooooo ... the big switch that switches on to 'brew' is there full voltage there or is that at the lower voltage as well ?
> 
> If the pump or even the switch cant be used to suit the cunning plan, then there is another way around the problem, that can utilize the lower pump voltage.


I'll resume tomorrow. The rest of the wiring is correct I think. I've just ran things temporarily until I'm happy everything works. Just need to find me a 240v switched live and then we are golden


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## Rakesh (Jun 3, 2017)

Sooo.... Does/will it work?


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## joey24dirt (Jan 28, 2017)

Rakesh said:


> Sooo.... Does/will it work?


If I can find a switched live giving me 240v it will  everything else is fine apart from this one feed haha


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## DaveP (Jul 14, 2017)

Yep... thats the grail, but there is a plan 'b' (for financial reasons it may involve getting a part from China.. but will look tomorrow)


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## DaveP (Jul 14, 2017)

And in the cold light of day....

There are several (well a few anyway) ways of using the seemingly lower voltage that the Sage uses to control the pump, the simplest would involve using a relay that's like the one you have but using a lower coil voltage, but if it really is 70v AC then that's a bit of a awkward voltage to use as it doesn't fit nicely into the scheme of things (the coil actuating voltages with allowed + / - and holding voltages) so If I was me for simplicity I'd use something like this ....

http://www.ebay.co.uk/itm/ASH-10AA-70-280VAC-to-480VAC-10A-Single-Phase-Solid-State-AC-AC-Relay-/191975481491?_trksid=p2141725.m3641.l6368.

There are other methods, but I recon this would be easiest for you.

But.. use the machine whilst your test leads are connected to the pump and note the voltage during the operation.


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## joey24dirt (Jan 28, 2017)

DaveP said:


> And in the cold light of day....
> 
> There are several (well a few anyway) ways of using the seemingly lower voltage that the Sage uses to control the pump, the simplest would involve using a relay that's like the one you have but using a lower coil voltage, but if it really is 70v AC then that's a bit of a awkward voltage to use as it doesn't fit nicely into the scheme of things (the coil actuating voltages with allowed + / - and holding voltages) so If I was me for simplicity I'd use something like this ....
> 
> ...


Thanks for this. I ran the pump yes and got a slow ramp up to 70volts. All I can think is it's something to do with the pre infusion??

So with the SSR is use that to take my 70v to ramp it up to 240v to operate my solenoid valve?


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## DaveP (Jul 14, 2017)

In short... yes

In long its nice and teckie as the 70v part of the circuit is sensed rather than taken, and our 240v is separate.

But hold fire on ordering as the slow ramp up 'may' be an issue...


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## DaveP (Jul 14, 2017)

Plan 'x' ,lol

A fudge to get things working and see if the valve has the desired effect.









This of course assumes (baddddddddddd) that the switch on the front panel is an on/off 230V 'ish


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## joey24dirt (Jan 28, 2017)

Yes I was going to try just energise the solenoid to make sure it hasn't packed up in the time it's been offline haha


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## joey24dirt (Jan 28, 2017)

Well this little project has been quite the head fart for me. Purely because of the control board inside the DTP making life that little bit more difficult.

I wanted the valve to be an auto feature on this so when you're pulling the shot it's closed then when you return to 'off' on the dial it opens and vents the pressure. Now either that's not a possibility with this machine or I need different components (and a new brain) to make that work with the voltages available.

So what myself and @DaveP have come up with is a new button on the sage. This will be used as a 'press and hold' type affair to vent the pressure, then release to return to normal use. I'll hopefully sneak it behind the tamper dock so it's easily available but not right in front of your face.....










This is the switch I'll use. Just need to wait for it to turn up from the bay then I can get cracking with fitting it 

Just want to thank @DaveP for his help with this one. I know it's not finished yet so expect more questions when I get stuck haha


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## joey24dirt (Jan 28, 2017)

....also with this switch in place.... it could be used as a backflush 

That's what I'm hoping for anyway


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## joey24dirt (Jan 28, 2017)

Well after much head scratching and then finally coming to the realisation that the electrics inside don't want to play ball, I've ended up with just a simple push on switch to operate the valve.

Yes it does help to vent the pressure and dries the puck slightly quicker but I'm not sure it's all been worth the effort. Luckily I've had most the expensive parts already from a previous machine so no real love lost. I'm just taking this as a good learning experience haha.

So this is what it looks like inside...










So top left we have the solenoid valve and related plumbing work. Top right (yellow heatshrink) is where the switch comes in and then the rest of the wiring goes to the bottom.

I picked up my live from the pump and then there was a bank of neutrals crimped together so I just went into those. I did install an extra earth wire from the switch just as a precaution. Don't want the body of it going live if something fails.

The switch is nicely out of the way anyway ....










So basically pull the shot, turn the dial back to standby position and then hit the button for a few seconds to allow the pressure and excess water to vent. Then to backflush this just use cleaning tabs as normal and then keep hold of the button to allow it to flow back through.

This would've been way more awesome if I could have made it more of an automatic process, but the sage electronics inside had other ideas haha.

Anyway again a huge thanks to @DaveP for his behind the scenes input and support. Much appreciated.

I'll update again after a week or so of use and see what sort of difference it has made


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## Rakesh (Jun 3, 2017)

The button does look quite cool and covert there though.


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## joey24dirt (Jan 28, 2017)

Rakesh said:


> The button does look quite cool and covert there though.


Cheers dude. I'm sure it will be a useful thing to have. Even if it's just to get the pressure out safely and cleanly when we go too fine and choke the machine up


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## lake_m (Feb 4, 2017)

What about an OPV mod? Ability to do low pressure extractions??? Go on....you know you want to....


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## joey24dirt (Jan 28, 2017)

lake_m said:


> What about an OPV mod? Ability to do low pressure extractions??? Go on....you know you want to....


Oh come on I've had too many sleepless nights over this. 1am I finished last night haha........

....I'll have a look though and see what they even are


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## khampal (Feb 6, 2017)

Good work, looking forward to hearing your experiences with it!

After you get the opv mod done, then you can add gravimetric controls to the list...


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## joey24dirt (Jan 28, 2017)

khampal said:


> Good work, looking forward to hearing your experiences with it!
> 
> After you get the opv mod done, then you can add gravimetric controls to the list...


Erm..... off to the google machine for research!


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## khampal (Feb 6, 2017)

joey24dirt said:


> Erm..... off to the google machine for research!


Haha I'm just kidding, I think the only machine I've heard of that has gravimetric controls is the victoria arduino black eagle. Though, being able to pull a shot automatically by weight on the DTP would be awesome.


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## DaveP (Jul 14, 2017)

> gravimetric controls


Hmmmmmmmmmmmmm.... providing the weight of the cup is a constant

Of course the 'funny' DTP electronics will cause an issue or 3 ..... but maybe a relay will help, lol

Hints and tips.

http://www.omega.co.uk/prodinfo/straingauges.html

http://www.omega.co.uk/prodinfo/straingauges.htmlhttp://www.omega.co.uk/prodinfo/straingauges.html


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## joey24dirt (Jan 28, 2017)

DaveP said:


> Hmmmmmmmmmmmmm.... providing the weight of the cup is a constant
> 
> Hints and tips..
> 
> http://www.omega.co.uk/prodinfo/straingauges.html


I need to get over this valve mod first


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## mcrmfc (Sep 17, 2016)

khampal said:


> Haha I'm just kidding, I think the only machine I've heard of that has gravimetric controls is the victoria arduino black eagle. Though, being able to pull a shot automatically by weight on the DTP would be awesome.


Gravimetrics are actually really easy and would be easier to do than say a pressure mod on this machine as it sounds a bit like it has its own logic around pre infusion and pressure control.

You just need an arduino a 3 quid scale, ssr and you can have my code for free.

Looking at how neat @joey24dirt has done this and with @DaveP on support I think you could do it super easy.

Bonus is you also get your shot timer for free.

Here is my early hack


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## joey24dirt (Jan 28, 2017)

mcrmfc said:


> Gravimetrics are actually really easy and would be easier to do than say a pressure mod on this machine as it sounds a bit like it has its own logic around pre infusion and pressure control.
> 
> You just need an arduino a 3 quid scale, ssr and you can have my code for free.
> 
> ...


Why  my brain was killing off this simple one I've just done.

It does sound seriously interesting though. I've often wondered about the arduino side of things as I don't have a clue about them.


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## Rakesh (Jun 3, 2017)

mcrmfc said:


> Gravimetrics are actually really easy and would be easier to do than say a pressure mod on this machine as it sounds a bit like it has its own logic around pre infusion and pressure control.
> 
> You just need an arduino a 3 quid scale, ssr and you can have my code for free.
> 
> ...


Wow that looks cool!


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## DaveP (Jul 14, 2017)

> I've often wondered about the arduino side of things


Simples 'ish ... well it is if some one has been kind enough to do the code, cos the code is the hardest part.


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## mcrmfc (Sep 17, 2016)

Here is my original post about it...like I say my efforts have been quite agricultutal simply as i have very limited time.

More than happy to help where i can if you are up for it

https://coffeeforums.co.uk/showthread.php?t=34926


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## khampal (Feb 6, 2017)

The ability to turn start and stop shots on the DTP from a microcontroller (like the arduino) would be cool, that would make controlling the solenoid valve automatically much easier too and could also enable regular timed volumetrics


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## joey24dirt (Jan 28, 2017)

All the above would be awesome......if......my kids were older lol. Two under two is tricky at the best of times. My projects are worked on between 10pm and 1am then up again at 6am for work. Just means my brain doesn't work as well as it should hahaha...

Something for the future though maybe.

Little update on the current mod though. You can now stop the shot bang on your target weight (well as close as possible) when you vent the pressure. Before I would run the shot to 32grams, stop the machine and let the drips from the pf get me up to 36grams. Obviously with the head being expelled if it's remaining pressure there's nothing to push the drips out for the last little bit.

I'm yet to discover if this is a good or a bad thing yet but we will see in due course


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## joey24dirt (Jan 28, 2017)

So I've had a few days to play about with this little mod. Probably pulled 10 shots so I can give it a mini review on it for others who may consider doing this.....

Pros..

1. Being able to stop the shot and hit desired target weight more accurately.

2. A good way to vent pressure when choking the machine. No more explosive pucks!

3. Reducing the amount of coffee soup left when the shot is finished.

4. Better control over the vented steam/liquid - this refers to the additional pipework installed going into the drip tray. Less mess = less stress 

5. Finally everybody loves a tinker so that will always be a pro lol

Ok now for the cons...

1. Only con that I've found so far is when you've pulled the shot and hit the button it causes the puck to fracture occasionally. So every now and then when knocking out some of it will stick to the basket. I'm hoping it's just the type of beans and the age of them (24 days old) so I'll see on the new batch I try.

All in all, now I've used it, I think it was a worthwhile thing to do.

Happy days


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## DaveP (Jul 14, 2017)

> Only con that I've found so far is when you've pulled the shot and hit the button it causes the puck to fracture occasionally.


If this continues to be an issue.... then maybe limiting the 'discharge speed' by reducing the id of the tube could prevent the shock.

Lots of nice engineered methods spring to mind (apart from squashing the pipe with mole grips, lol)


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## ATZ (Aug 4, 2017)

Shame you couldn't link it to the control button but I like the hidden push button!


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## joey24dirt (Jan 28, 2017)

ATZ said:


> Shame you couldn't link it to the control button but I like the hidden push button!


I know it is a shame. I'm sure someone out there with more grey matter then me could figure it out ( @DaveP )


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## joey24dirt (Jan 28, 2017)

ATZ said:


> Shame you couldn't link it to the control button but I like the hidden push button!


I suppose though at least I have the option to use it or leave it


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## ATZ (Aug 4, 2017)

joey24dirt said:


> I suppose though at least I have the option to use it or leave it


My experience with the DTP so far is that I don't feel like I'm missing a 3 way valve. Pucks come out whole and largely dry, I just leave the PF on for a little while post extraction. My only really "soggy" pucks have come when I've choked it tbh, this is when the 3 way valve would come into it's own.


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## joey24dirt (Jan 28, 2017)

ATZ said:


> My experience with the DTP so far is that I don't feel like I'm missing a 3 way valve. Pucks come out whole and largely dry, I just leave the PF on for a little while post extraction. My only really "soggy" pucks have come when I've choked it tbh, this is when the 3 way valve would come into it's own.


Yes it's true that if left it will naturally dry itself and come out no problem. This was just a "wonder if I could" type of project. No real need for it but did it anyway lol.

I've switched beans tonight and found that the puck comes out clean now. No fracturing or getting stuck so hopefully it stays that way 

You have a mazzer also right?


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## ATZ (Aug 4, 2017)

joey24dirt said:


> Yes it's true that if left it will naturally dry itself and come out no problem. This was just a "wonder if I could" type of project. No real need for it but did it anyway lol.
> 
> I've switched beans tonight and found that the puck comes out clean now. No fracturing or getting stuck so hopefully it stays that way
> 
> You have a mazzer also right?


Oh I totally get the want to try this mate, I love a bit of tinkering.

I do, not quite sure I'm using it to it's full potential yet


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## joey24dirt (Jan 28, 2017)

ATZ said:


> Oh I totally get the want to try this mate, I love a bit of tinkering.
> 
> I do, not quite sure I'm using it to it's full potential yet


Oh really whys that? Maybe you need to paint it bright orange like mine 

I found when I moved to the mazzer that was when I had really soupy pucks. With the sage I had none of this haha


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## mctrials23 (May 8, 2017)

The only time I have ever had an issue with even damp pucks is when I clog the machine. Beyond that I just wait a few seconds after the shot is finished and its all fine. A really gentle tap on the knock box takes the puck out whole with no breakage at all.


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## Mr Kirk (Oct 5, 2017)

@joey24dirt I'm no electrician and haven't fully understood the whole thread.

But if you're struggling to get full voltage from the switch when in the espresso position, surely there's a relay available which has a double positive input to produce a single positive output?

So it would have an input from somewhere giving 240v and only when it detects the second input of 70v from the espresso switch it will give a full 240v output to power the valve to closed position?


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## joey24dirt (Jan 28, 2017)

Mr Kirk said:


> @joey24dirt I'm no electrician and haven't fully understood the whole thread.
> 
> But if you're struggling to get full voltage from the switch when in the espresso position, surely there's a relay available which has a double positive input to produce a single positive output?
> 
> So it would have an input from somewhere giving 240v and only when it detects the second input of 70v from the espresso switch it will give a full 240v output to power the valve to closed position?


It's all low voltage circuits inside. Obviously a straight 240v coming in but I couldn't wire into that direct without the need for an extra switch to energise the valve.

I'm sure if I had more time I could've found a way around. But the easy option was to add the switch. It's part of my routine now so I don't even realised I'm doing it now haha


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## ajohn (Sep 23, 2017)

I take it the DTP doesn't have a 3 way valve? Surprises me but suppose they had to add more as extras on the BE.

Now I have a Piccino I can see that the principle the valve uses is pretty simple.









The main part is above PIC97 , a separate solenoid. I don't know if it's a normally open one which would mean that it's energised when ever the pump is running for a brew or a normally closed one that always energised when a shot is being run. The liquid flow paths are short - I'd guess that is important.








Going on that diagram the Piccino works via magic - one thing the parts list doesn't show is how it's all piped together. The heater you can see is the brew boiler mounted directly on the group head. PC111 is definitely the 3 way outlet. Can't see how they could do it without a solenoid valve as mentioned.

The wiring diagram shows just 2 solenoids. One called group and the other inlet.

Going on the BE nice to have but sludgy pucks result in more grounds being sucked back into the machine and there is a limited basket fill range for a perfect puck.

John

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## MWJB (Feb 28, 2012)

ajohn said:


> Going on the BE nice to have but sludgy pucks result in more grounds being sucked back into the machine and there is a limited basket fill range for a perfect puck.
> 
> John
> 
> -


Sorry, I don't see the logic there. Prior to the 3 way solenoid doing it's thing, there will always be liquid & grounds above the puck. If your dose sits high enough, then all this liquid & any grounds within in are hoovered off. Your puck appears drier.

If your dose sits lower, then liquid is left on the puck, along with any grounds therein.

Not sure why this would mean that either scenario would suck more, or less grounds back into the machine.

A great cup can be brewed with either a wet, or a dry puck.


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## ajohn (Sep 23, 2017)

From flushing the machine which I always do to heat up the portafilter I can see that more grounds get sucked back into the machine if the puck turns out to be sludgy also from cleaning out the drip tray.

I tried a bean for a while where the single basket wouldn't hold enough and the double held too much. This is why I feel they should offer other sizes of basket. One in the middle of the ones they do and ideally a triple.

John

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## joey24dirt (Jan 28, 2017)

ajohn said:


> From flushing the machine which I always do to heat up the portafilter I can see that more grounds get sucked back into the machine if the puck turns out to be sludgy also from cleaning out the drip tray.
> 
> I tried a bean for a while where the single basket wouldn't hold enough and the double held too much. This is why I feel they should offer other sizes of basket. One in the middle of the ones they do and ideally a triple.
> 
> ...


The IMS baskets for a la spaz will fit with a small amount of tweaking.


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## ajohn (Sep 23, 2017)

joey24dirt said:


> The IMS baskets for a la spaz will fit with a small amount of tweaking.


I did look at that option, tricky crunching up the edge but the best option would be for sage to make say a 12-14g basket or maybe a touch less.







I do think it's good of them to supply slightly larger baskets than the norm with the machines though but a 5g gap in them is pretty large. I think the standard larger sizes reflects modern tastes - longer drinks.

Touches on another reason for picking a Piccino to play with 6,7,12,14,21g baskets. They tell me not many 6's go out. For some reason the 12 has a much sharper lip part way down the side than the others. Fine in a Facino portafilter but not in a certain one not made by them. The man who sold me that is telling me that baskets are a pain but also pointing out that he doesn't state that it's ok for OEM baskets - he does call it a Facino portafilter though.







.

John

-


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## PPapa (Oct 24, 2015)

ajohn said:


> From flushing the machine which I always do to heat up the portafilter I can see that more grounds get sucked back into the machine if the puck turns out to be sludgy also from cleaning out the drip tray.
> 
> I tried a bean for a while where the single basket wouldn't hold enough and the double held too much. This is why I feel they should offer other sizes of basket. One in the middle of the ones they do and ideally a triple.
> 
> ...


How many grams are you putting into a double?

You can use IMS baskets for La Spaziale, if you are confident with pliers. That didn't work out for me well.


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## ajohn (Sep 23, 2017)

From what I can see the Sage filters are fine in their stated range - might get a film of water at or below the lower limit. Go down to 12g and the usual result is a soggy mess..

I suppose in a sense it could be argued that it doesn't matter 'cause coffee comes out - I don't see it like that. A soggy mess spoils the experience and the end result should be a drink that suites the user what ever beans they choose to use and pucks should come out cleanly.

John

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## MWJB (Feb 28, 2012)

ajohn said:


> From what I can see the Sage filters are fine in their stated range - might get a film of water at or below the lower limit. Go down to 12g and the usual result is a soggy mess..
> 
> I suppose in a sense it could be argued that it doesn't matter 'cause coffee comes out - I don't see it like that. A soggy mess spoils the experience and the end result should be a drink that suites the user what ever beans they choose to use and pucks should come out cleanly.
> 
> ...


If you're putting 12g in a basket rated for 15-18g then it likely will matter, extraction will be off irrespective of sloppypuckness. Why not drop to 9g or 10g and use the single?


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## ajohn (Sep 23, 2017)

MWJB said:


> If you're putting 12g in a basket rated for 15-18g then it likely will matter, extraction will be off irrespective of sloppypuckness. Why not drop to 9g or 10g and use the single?


If you read my posts there would be no need to answer that.

John

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## MWJB (Feb 28, 2012)

ajohn said:


> If you read my posts there would be no need to answer that.
> 
> John
> 
> -


Humblest apologies, please forgive me, there are many posts on the forum & I have clearly squandered my memory by contaminating it with other people's thoughts & ideas. I shall rectify this immediately by printing off, scanning, collating all your posts & updating it every 10 minutes, so that I will never fall out of step again.


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## Mrboots2u (May 10, 2013)

ajohn said:


> If you read my posts there would be no need to answer that.
> 
> John
> 
> -


Too much coffee? Manz is just trying to help.


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## ajohn (Sep 23, 2017)

MWJB said:


> Humblest apologies, please forgive me, there are many posts on the forum & I have clearly squandered my memory by contaminating it with other people's thoughts & ideas. I shall rectify this immediately by printing off, scanning, collating all your posts & updating it every 10 minutes, so that I will never fall out of step again.


Sorry, caught at a very bad extremely irritated bad tempered moment. I had mentioned that with one bean I bought that the single wasn't big enough and the double too big. ;-) I finished them off via drinking weaker coffee.

John

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