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Author Topic: TDC3 139 Volts on R1 when not in use  (Read 1136 times)
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Posts: 315

« on: February 02, 2019, 05:37:26 PM »

I did write about it when it was 39 volts 10 years ago,7149.msg73691.htm

But I changed the circulation pump a few months back and it has a more sensitive pump and so is flashing error all the time as it is getting 130v.
I used a Wilo Yonos Pico pump from Screwfix (It stopped on a sunny Sunday!)

Has my TDC3 had its day and should I replace it?

From the previous thread the problem is that it is a Solid State Relay
The manual says:
"Relay R1 is only suitable for standard pumps (20-120VA) which are
speed-controlled viathe controller. The internal wiring of the controller
is such that residual currents flow over relay R1 even in the rest
condition. Therefore under no circumstances may valves, contactors
or other consumers with low power consumption be operated on this
This warning doesn’t appear in the manual anymore – so maybe they have changed it.

So what is the TDC3 replacement that does Tank and Pool (type 13 on TDC3?)
Anyone using one and monitoring the output via a relay and 1-Wire or the likes?

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« Reply #1 on: February 03, 2019, 07:41:42 AM »

It's not the TDCs fault. The clue is in the "Relay R1 is only suitable for standard pumps".
The Wilo looks like an intelligent pump with on-board electronics. Therefore trying to drive a PWM pump from a PWM supply is only going to end with one or both devices suffering failure - assuming it ever works in the first place.
« Last Edit: February 03, 2019, 07:44:33 AM by Antman » Logged

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« Reply #2 on: February 03, 2019, 09:37:46 AM » please excuse my ignorance and terminology here...

I am running a Grundfos UPS2 but I don't operate it in smart mode. One of the LEDs is always on which I think can be traced down to the residual current.

My questions are

1. Does the residual current mean I'm using electricity? I have a phantom ~20w draw.
2. Is there anything that can b put before the pump that would "soak up" that residual current so my led isn't always on?


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« Reply #3 on: February 03, 2019, 10:08:52 AM »

Slightly different but on my home made energy diverter I use Solid state relays and on a couple of occasions I have put a resistor on the output to reduce the voltage. One example was for the input to a trace inverter charger that would see the voltage and so think it was connected.

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« Reply #4 on: February 25, 2019, 10:55:46 AM »

My Solution was to buy a New Controller.  The MTDC5 now has 2 real relays and everything is working as it should be.  The wiring was exactly the same.  The TDC3 is there as a backup!
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