Hi Andy,

ah yes that's true, I just checked my PID manual and indeed you can set the range to whatever you want when using voltage/current inputs.

Well I guess all I need now is a transducer.

Regards,
dsc.

Hi everyone,

I finally managed to seal those damn fittings on the outboarded pump and did so with the use of something called Loctite 542 (thread sealant). Basically it's a fluid that you apply to the threads and it hardens if there's no air around (when the fittings are tightened). Looks like soy sauce when liquid and like jam when hardened:





The instruction says it takes 15min for it to seal, but after only 5min I couldn't move the damn fitting, so I guess it works even faster. I think it's a really good product for 'permanent' seals, the ones you won't be touching for a long time.

Anyway nothing leaks any more and I didn't have to use the oh so annoying teflon tape, so I guess I'm happy.

Regards,
dsc.

Hi again,

the transducer is here!!:)

Bought it off ebay, it's a new Vogel Pumpen pressure transducer with a 0-10bar range and 4-20mA output, complete with cable plug:



I'm now only waiting for a 1/4" BSP female-female socket and for the Fuji PIDs from Nicholas, so I can swap one of them with my current PID and use that one to display the pressure.

Should be fun.

Regards,
dsc.

Hi guys,

well it was a bit of fun, but not entirely. I've installed the pressure transducer this morning and oh boy it takes a while to get a proper read out. With a blank disk in the PF it took around 5-6s to get a read out of 8.5bar (pump setting). Don't know why it works like this, but I'll be switching to a normal dial gauge sometime in the future. I'd love to get a proper panel-install high precision one, but sadly the cutout in the front panel of the Elektra is 60mm and the industrial standard is 63mm:| And even if I somehow manage to fit one in I will have to re-route the hot water pipe at the back of the gauge as it runs straight through the middle where a normal single dial gauge would have it's entry.

All the fun ended when my machine started acting strange and the autofill function began to misbehave. I have no idea why it happened but it was autofilling for a very long time after I used around 200ml of water from the hot water line. The pump was running for around 30-40s and suddenly stopped, so I though what the hell maybe the boiler was way below level? Tried it again and the same thing happened although this time I almost shut down the machine as it was seriously taking too long. On top of that there was almost no water coming from the group, as if it was running on inline pressure all the time (even though the pump was engaged). Tried pulling a shot and even managed to get something out, although I knew it wasn't right. The boiler pressure wasn't raising and everything seemed to work normally (except for the weird autofill and group flow behaviour). I turned the machine off and partially drained the boiler through the hot water tap, checked the level sensor, descaled it (it was clean but I did it anyway) and put it back together. After turning it on it started filling the boiler again, but this time it wouldn't stop for a good minute or so. When it finally de-energised the pump all the LEDs above the buttons started flashing and it wasn't doing anything. So I removed the pressure transducer, put the pipes back as they were and checked the level sensor connections (on the cable and on the PCB behind the buttons). All looked ok, so I turned it back on, but forgot to turn the inline water supply:O This means I ran the pump dry for a few seconds after realising how stupid I am (brand new pump) and gave myself a proper whack on the head to pull myself together. Fortunately it looks like the pump is alive and kicking, probably minimal (or no) damage done to it. It did have around 2m of pipes on the inlet (+the water filter) all filled with water, so I guess that somehow saved my ass (and it only ran for a few seconds). It's not making any strange noises and seems to work well giving proper pressure and not leaking.

I don't know what caused that strange behaviour but I do know that I need a dial gauge, a new proper long hose to connect the machine to the JG fitting I have on the end of the pump tubing and I still have to fit the TC on the boiler.

Regards,
dsc.

Hi again,

in the end I've decided to mount a TC on the boiler to control pressure, just like Nicholas did on his Elektra here:

http://www.home-barista.com/espre...mine-t8623-80.html

I've been thinking of mounting the pressure transducer somewhere near the boiler as well and even found a spot:



but unfortunately the fitting on the pipe from the boiler is a compression one and the PT won't seal against it. I've left this for now and might pick it up sometime in future if the PT is still free and not used for anything.

I've removed the pstat and pretty much half of the back piping to turn the 3-way junction around and attach the water inlet pipe to it's bottom. With the smaller detachable metal frame removed I dry-fitted the SSRs inside the machine and I've got two options:



or



The first one looks good and should work well, the only thing I need are some metal backing plates to attach the screws to something as the pump brackets have quite big holes in them.

Everything is ready to put back together, I'm only waiting for SSR covers and thermal pads and I can test it out probably tomorrow.

Regards,
dsc.

FWIW, I have a 40 Amp SSR on my setup now, and it's bolted to an aluminum backplate and heat sink. It still gets to 50C on startup, and reaches a steady-state of around 30-33C. If you're thinking of using that SSR for the heating element, I would warn you that I'll bet you'll shorten the lifespan a lot in either of those locations. But, I don't have any experience with that brand (my 40A is an Omron) or voltage, so who knows. I could see the smaller draw at the higher voltage producing less heat.

Hi Nicholas,

the SSRs I have are all 50A, 400V models and with a 2300W heater they should draw more than 10A. This is 1/5th of their maximum current, so I'm guessing it shouldn't be that bad even inside the machine. Sure they will get warm/hot, but it should be less than yours. I will try to measure their temps near the base during the warm-up stage, we will see what the TC is going to show. Personally I do like the idea of the SSRs sitting inside the case as this means I don't have 230V/10A cables going inside or near the PID box, it's only going to be DC wires sticking out of it (and the power cable of course).

I do have one question, how did you wire the your SSR? After removing the Pstat I'm left with two pairs of cables, two blue ones and two brown ones. I'm not sure why as I thought there's just going to be one pair (circuit being closed with the contacts of the Pstat on the brown cable), but it looks like it's a double-break kind of combo, contacts on both the Neutral and Live. I was thinking of joining the Neutral cables that came from the Pstat together and installing the SSR on the Live cables only. Did you do the same?

Regards,
dsc.

Yes, that's what I did, I believe. I took out the white (on mine) cable that went from the heater to the pressurestat and threw it away, and hooked the white cable that made the full run to the pressurestat straight to the heater, and then ran the red pair out to the SSR and switched them.

For what it's worth, I took Mark's advice and disconnected part of my heater, so it's running about 12A on my 40A SSR. That's not 1/5 the rating, but it is close to 1/4. It's definitely something to keep an eye on (if it works well, I'll have to get a 50A Crydom SSR ).

Hi everyone,

few things got cleared up during my chat with Nicholas yesterday and now I know why my machine was behaving oddly a few days ago. It turns out that the 3-way junction can't be turned 90deg to allow for bottom water connection as the pressure gauge connector has a very small diameter which slows down the flow. This is why nothing was coming out of the group when I was engaging the pump and why the boiler was taking so damn long to fill. This was also the reason why the PID hooked up to the PT was showing a very slow pressure build up. So I ditched the whole turn-90deg idea and went back to the original setup and even managed to figure out how to connect the PT. The only thing I need to do now is to find a way to convert the 1/4" compression fitting to a normal 1/4" threaded fitting as I doubt the compression fitting will seal against the flat bottom of the PT.

I also decided to mount the SSRs using option 2 above, screw them directly to the bottom of the frame. The reason behind this is quite simple, the plastic covers on the SSRs won't work if the SSR is positioned on it's side (if they sit flat even when you get water dripping from the top it shouldn't be too bad). Unfortunately this means I have to drill the holes for the screws and I didn't have enough time yesterday to do it. I did however tidy up the cables inside using cables ties and cable sleeving, so it should be a breeze to finish it off.

Regards,
dsc.

To seal something flat against a compression fitting, try a copper washer and a lot of pressure (assuming the threads are compatible). I sent you a bunch of extra copper washers that should fit right on the tip of any of the male compression fittings on the boiler or junction. Just be careful to center it over the tip properly when you thread it on. This is how the TC adaptor that I sent you fits onto the boiler, AFAIK. It's flat on the inside as well.