# Crouzet PNRU relay



## Peewee0413 (Oct 18, 2012)

460 Delta said:


> Does anyone here have any experience or used one of these relays? I’m wondering if it would work in a poly tank with a suspended “ground” probe that goes nearly to the bottom. Supposedly you’re to use a metal tank, but I really want to use a polyethylene tank instead.


Would need a common electrode as well as the level probe. *Picture = One as single point, and one as a ground. Depending on the wiring of these type of relays, you may have to jump the high/low out or use 3 probes if your running a pump ( one probe turns on, the other turns off). Either single point or 2 point control, in a non conductive tank, you would need a common electrode.


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## 460 Delta (May 9, 2018)

Peewee0413 said:


> Would need a common electrode as well as the level probe. *Picture = One as single point, and one as a ground. Depending on the wiring of these type of relays, you may have to jump the high/low out or use 3 probes if your running a pump ( one probe turns on, the other turns off). Either single point or 2 point control, in a non conductive tank, you would need a common electrode.


I would of course need both high and low so three probes. I’m concerned that the sensitivity may be too low not using a metallic tank.


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## Peewee0413 (Oct 18, 2012)

460 Delta said:


> I would of course need both high and low so three probes. I’m concerned that the sensitivity may be too low not using a metallic tank.


That's what the extra probe is for, it gets a ground wire connected to it. the other two probes would be your high/low


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## 460 Delta (May 9, 2018)

Do you have direct knowledge, as in have you used one of these before?


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## Peewee0413 (Oct 18, 2012)

460 Delta said:


> Do you have direct knowledge, as in have you used one of these before?


I've done many different relays but not a Crouzet. Have even used 2 relays and 4 probes. high, low, low low, and ground. Used one relay for high and low fill control, and a one relay for a low low alarm/fault. I have only programmed Crouzet PLC's.


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## paulengr (Oct 8, 2017)

IFM Efector makes a nice continuous one where you can set relay outputs too. It’s reasonably priced.

What you are looking at is also used as a moisture probe in motors. Look at Macromatic for an example.

But I also just put in a Vega radar system. Let me tell you I’ve done tons of ultrasonics. They work OK but don’t like foam, splashing, fog, rain, steam, etc. Radar is the best but very expensive. So it only gets used in really bad situations or deep pockets. Vega brought the price down though to the point where high end ultrasonics are now much more expensive. It’s really, really nice with all kinds of options. In my case as a flow meter application when I adjusted the calibration I stood 25 feet away with my cell phone and did it with Bluetooth. So simple.


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## just the cowboy (Sep 4, 2013)

460 Delta said:


> Do you have direct knowledge, as in have you used one of these before?


I have used ones like the one pictured and they work good if the product being sensed is thin and can run off. I had issues with bridging on creams and paste.
If product is thick you can just install a probe as ground and use that as reference instead of metal tank. You can place it so you have good conductivity but far enough to no bridge across.


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