Zurn converter

[Jnewell]

I am having an issue with a zurn converter, from 100-240 volts a/c to 7.6volts dc. Every time I put it under load the voltage on the dc side disappears, take the load off and it puts out the correct voltage. I have switched the part out and had a part that was in town that did the exact same thing. We found a different part, which worked for about 2 weeks and once again it’s doing the same exact thing. I talked to the Zurn SR tech and he said this was impossible and he wanted the part back so I took video and sent it back to him. I’m thinking about throwing a power quality meter on it to test for anything abnormal on the a/c side, but before I do that I want to check to see if anyone has had any experience with these that could bypass anything unnecessary

 

[LarryFine]

Sounds like an automatic overload shut-down. Can you partially load it?

 

[hbiss]

Output is 7.6 VDC at what current? Read the label or spec sheet. What is the current draw of the device you are connecting to it? Answer these two questions!

Your test procedure is to connect a DC ammeter between the output and your device.

-Hal

 

[Jnewell]

After looking up some specs online it looks as if they have to many sensors on 1 converter . We are going to split the circuit, add another converter and I will take some amperage readings then and I will update. Thank you for the leads

 

[Jnewell]

No dice... I split the circuit and both of the new converters are doing the exact same thing. I put my amp meter on max mode DC and it read 1.2A. I am starting to think it is in the wiring or the sensors, but I don’t have enough experience with these to tell. Please help

 

[synchro]

Are you sure that all of the loads are connected with the correct DC polarity?
Also, did you measure the output voltage of the converter when you made the 1.2A measurement? This is to make sure that the converter didn't "foldback" the output voltage (i.e., drop it to nearly zero volts) to protect itself.

 

[GoldDigger]

Are you sure that all of the loads are connected with the correct DC polarity?
Also, did you measure the output voltage of the converter when you made the 1.2A measurement? This is to make sure that the converter didn't "foldback" the output voltage (i.e., drop it to nearly zero volts) to protect itself.

:thumbsup:

For all you know you could have two or more direct shorts in the wiring or two or more shorted sensors. In this situation you will never trip an overcurrent device since the power supply limits its output current. The foldback behavior means that the current drain from a still source will be far higher than 1.2A.

The only symptom that does not fit very well is that one converter worked for a week. Possibly the failure is intermittent?

Troubleshooting from here, as I see it, has two parts:
1. Test the converter(s) with a resistive load to make sure it is still working properly
2. Test the wiring harness with no sensors attached and if it is OK, add sensors until the output shuts down, measuring current at each step.

 

[hbiss]

Is this a power supply for urinal flush valves and faucets?

https://www.zurn.com/products/finish-plumbing/faucets/manual/parts-accessories/p6000-hw6

-Hal

 

[Jnewell]

Yes Hal that is it, but instead of 2A max it is 1A min with a white label instead of blue. The “fold back” makes the most sense because even though I get bad parts all the time it is unlikely to get 4 with the same characteristics and I thought about a shorting possibility but the Sr. Tech from Zurn told me Basically it was impossible. So thank you for your expertise and for the help, I will post when I make more progress.

 

[pjones]

Yes Hal that is it, but instead of 2A max it is 1A min with a white label instead of blue. The “fold back” makes the most sense because even though I get bad parts all the time it is unlikely to get 4 with the same characteristics and I thought about a shorting possibility but the Sr. Tech from Zurn told me Basically it was impossible. So thank you for your expertise and for the help, I will post when I make more progress.

Why is a short impossible? A rub through, a failed component on a circuit board, a piece of wire strand sticking out of a bad connection.... shorts come in all types, I see them often in the equipment that I service, I don’t see why it would be any different when it comes to plumbing fixtures and their respective wiring.


Sent from my iPhone using Tapatalk

 

[hbiss]

From the power supply description:

"The hardwired power converter is a 7.6 VDC regulated, 2.0A power supply that will operate up to: (8) ZEMS or ZEMS-IS sensors/actuators, (8) ZESS sensors/solenoids, (8) sensor faucets, or (8) Pint urinal valves."

So I have to think that a 1A supply (which I'm not seeing that they make) will operate up to 4 devices. So my question is, do you have four or fewer devices on the power supply and are they Zurn devices? Because other than Zurn devices may draw more current.

Was the replacement power supply also 1A? Wonder why they only make 2A now?

The only symptom that does not fit very well is that one converter worked for a week. Possibly the failure is intermittent?

My thinking too is that maximum current will be drawn if all devices operate at once. So a simple explanation might be that the restroom use was light during that week.

-Hal

 

[GoldDigger]

From the power supply description:

"The hardwired power converter is a 7.6 VDC regulated, 2.0A power supply that will operate up to: (8) ZEMS or ZEMS-IS sensors/actuators, (8) ZESS sensors/solenoids, (8) sensor faucets, or (8) Pint urinal valves."

So I have to think that a 1A supply (which I'm not seeing that they make) will operate up to 4 devices. So my question is, do you have four or fewer devices on the power supply and are they Zurn devices? Because other than Zurn devices may draw more current.

Was the replacement power supply also 1A? Wonder why they only make 2A now?



My thinking too is that maximum current will be drawn if all devices operate at once. So a simple explanation might be that the restroom use was light during that week.

-Hal

A very credible hypothesis. And once the foldback response to overcurrent is triggered the "idle" load on the circuit could keep it from resetting until power is cycled or all loads are disconnected.