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By koruki
#197803
Hi guys,

Bit of a noob with this one but I'm usually pretty logical and this one doens't make sense. So I got one of these to control my hot water cylinder. More than enough amps to handle the load.

I tested the bridge connection and everything is acting as expected. Powered by 12V DC, powered on and the meter it showing its bridged, power off and it shows no connection. Connected to my 240V AC and before I even power on the DC input, the connection is already bridged. I verified this with a AC scanner. Thinking I had wiring problem, I disconnected the relay and did another scan, the cable leading to the hot water is no longer live.

Anyone have any suggestions on what I can check or why its behaving like this?
By paulvha
#197807
A solid state relays is straight forward connection. A couple of questions:
How did you connect (4 = GND, 3 = 12VDC, 2 life-wire from 240V, 1 output to boiler, other side of boiler to NULL ?
what do you mean with "the cable leading to the hot water is no longer live? ". Is the boiler not working anymore ? Is there no 240V ?
Is the SSR broken or still working ?
I wonder how you measure in first instance that it showed bridged with a meter. The output is regulated with a TRIAC, which needs a minimum load in order to work correctly. A simple meter would not provide that, and it needs an AC voltage.

regards,
Paul
By koruki
#197809
Hi Paul,

Thank you for the reply. The boiler is fine, what I meant was the wire leading to it was live before I turn on the DC input. To confirm it wasn't live before the relay was connected, I disconnected the relay and checked, so the bridge is definitely coming from the relay.

For connecting, I took the live connect to the boiler and broke using the relay as the bridge. Pretty straight forward as you said.

In terms of what I was checking with the meter, I was using it to check ohm over the bridge. It was showing nothing when Dc was off, once DC input was switched on, it bridged, though there was showing some resistance.
By paulvha
#197814
weird.. I advice you to try connecting a lamp (say 40W) instead of the boiler and see what happens. It could be that you relay is broken. Although It is not a mechanical relay, also test what difference is in 240V output, if you connect and disconnect the 12V DC.
By n1ist
#197823
If you are using a tic-tracer or other non-contact detector, or even a high-impedance voltmeter, you can pick up phantom voltages (leakage, capacitive or inductive coupling). Try with a low-impedance meter or put a load (like the 40w bulb mentioned above) across the line and measure it that way.
/mike
By koruki
#197954
Thanks again for the helpful insight. I did a test with a light bulb previously before doing the install on the boiler and it worked as expected. There was about several months in between so .. I could do it again to confirm its not broken
By koruki
#198059
Off topic but I went to go find another one in case my one wasn't working and ended up finding a inline wifi controller relay with enough amps to drive the boiler. Win win situation.