ITO/Leva! Controller - Q&A + Experience - Page 13

Need help with equipment usage or want to share your latest discovery?

#121: Post by jaibm »

Many thanks for the in depth explanation Dietmar.

I experienced the same failure mode - constant maximum output.

Sounds like it might be difficult to find a reliable no brand sensor. I had a look but can't find any of the older 7mm sensors, so I'm giving the Honeywell a shot. I have used this PX3 series of sensors in other applications before and they have been trouble free.

It should be here from Mouser within the week and hopefully I can report back some good results. Perhaps this will be a good option for others going forwards.


#122: Post by jaibm »

The new sensor arrived last Tuesday, and of course was a simply install with the same thread and connector as the previous sensor. There did not seem to be any offset to take into account even though it is a sealed sensor.

I re-ran the pump pressure test program, and straight away the pressure profiling is running well without any further manual tuning. I've been running the 1 bar preinfusion/9 bar shot all week to great success. Perhaps I'll just need to fine tune the proportional gain a little further to avoid some mild pump oscillations during the preinfusion stage.

Looking forward to delving into some further customisation/experimentation now that all the hardware is up and running :)


#123: Post by sandc »

Thanks for the feedback. I'll then recommend this Honeywell sensor for the time being (hopefully the cheap Chinese transducers will get better again). Software & Circuits can provide matching leads and fittings for ito.


#124: Post by detonate »

Hello all! I recently started to rebuild my Silvia V6 with the beautiful Ito/Leva! kit. I already can join with a malfunction pressure sensor. After a few hours of testing the sensor is giving max output.

So the PX3 series, like the PX3AN2BS250PAAAX which suits the most i think, is the way to go now in your opinion? Thank you in advance!


#125: Post by sandc »

> the PX3 series ... is the way to go now in your opinion?

It's available (,,,, it's comparatively inexpensive and some models in this series offer the same electrical connection (Delphi Metripack 150) and threads (1/8" NPT) as the Chinese sensors - which makes those a simple 1:1 replacement. There are of course other pressure sensors that would work just as well, such as the MLH series mentioned in the manual. Those might require a different plug or they might have a different pressure port (for example 1/4" threads). Note that you have to be careful if you select a model from the PX3 series. Every letter in the article number means something. Many would not work with ito or would be inconvenient. The datasheet contains an explanation of the letters in the number. These should be the best matches (no liability assumed):

PX3AN2BS016BSAAX (16bar range)
PX3AN2BS020BSAAX (20bar range)
PX3AN2BS025BSAAX (25bar range)
PX3AN2BS200PSAAX (200PSI range)
PX3AN2BS250PSAAX (250PSI range)
PX3AN2BS300PSAAX (300PSI range)

These should work as well but would require a -1 bar offset setting in the leva! firmware (because they measure ambient pressure as ~1bar at 0m NN):



#126: Post by Cafiza »

Dear Sandc, Dietmar,

A while ago i purchased the ITO kit. After a few months i finally had the time to assemble. It was really nice to do and i liked the package as a whole.

I installed the hardware and flashed the ATM. I went to the quickstart guide of the firmware manual but i experienced a non-functioning pump. Group head valve is working well. I started to check the wiring again and i noticed i switched the N and L phases on the side of the power switch... yes i know... both relays on the ITO are looking fine but i do suspect i short-circuited...

Is it possible to resolder one or both relays on the ITO and fix it? Or are there more components involved in the possible short circuit?


#127: Post by sandc »

> relays on the ITO are looking fine but i do suspect i short-circuited

A short-circuit current over relay #1, due to a mistake with the connection of mains phases, will destroy it. No flash, no bang, just dead in an instant.

> are there more components involved in the possible short circuit?

Not normally. There is a fuse (F1) but that's too slow to protect a semiconductor from a short-circuit. It should still be ok. The black TVS diode between the pins of the SSR should not be affected. If you have a continuity tester: It should not conduct in any direction.

> Is it possible to resolder one or both relays on the ITO and fix it?

Open a support ticket to have the defective relay replaced by Software & Circuits. Expect costs of 20€ for part & labour (+ shipping). If you can replace it yourself (requires desoldering skills) or have somebody locally who can replace components, here are links for the Omron G3MC-201PL DC5: ... -A-8074649 ... Z93A%3D%3D ... DC5/368909


#128: Post by Cafiza »

Thank you very much for the explanation and offer to help! I'm glad to hear it is replaceable and i will replace relay #1 in a few days when they arrive!


#129: Post by Cafiza » replying to Cafiza »

I can share that i have successfully replaced relay #1. When starting the machine again it fired up the pump like it should! Finally i can experiment with the feature set of Leva!!

As i am rerouting the wiring to make the inside neat and tidy it brings me to another question. As i have a V6 there i have a insulation shield for the boiler. I removed it for application of the Tsic. Now im wondering what are the main disadvantages of using the insulation with a temperature sensor? if i remember correct the manual says not to use it. I can imagine it has a possitive effect on the case temp, something which is even as importent with al the added components.


#130: Post by Pflunz »

I would guess the main disadvantage is for the PID. Since you only can heat the boiler, and not cool, it's not a linear system. You have to wait until the boiler cools down. This means, with a non insulated boiler you can set the PID more aggressive, since an overshot ist not as bad as with an isolated boiler.