Tap Relay

Legin · Mar 2, 2019

I fitted a shower to my T6 the same one as factory and whilst I was at it fitted a relay to protect the tap microswitch.
From what I have read the tap fails due to the contacts failing so hopefully this will mean I dont suffer the same fate now the relay takes the load.

I fitted it into the the tap flying leads at the tap and once you take the drawer out isnt that difficult.

sidepod · Mar 2, 2019

Wow. Over achieving or what? Good effort.
Are the contacts of the tap really under rated?

Legin · Mar 2, 2019

sidepod said:
Wow. Over achieving or what? Good effort.
Are the contacts of the tap really under rated?

I maybe wrong as I havent seen the contacts myself but I believe folks get them going again by cleaning the contact faces. This usually means the arcing is excessive due to small contact area and or low contact pressure for the current. Relay far more substantial.

jliungman · May 24, 2020

Legin said:
I fitted a shower to my T6 the same one as factory and whilst I was at it fitted a relay to protect the tap microswitch.
From what I have read the tap fails due to the contacts failing so hopefully this will mean I dont suffer the same fate now the relay takes the load.

I fitted it into the the tap flying leads at the tap and once you take the drawer out isnt that difficult.

Sorry for jumping into thread this late...

How would a "failing" tap relay behave? I seem to be getting very little voltage at the pump when everything is connected and tap is on, but full 12 volts when I disconnect the pump and measure with zero load. This seems consistent with your theory of small contact area. The pump itself seems to be ok (removed and tested it). Any ideas?

Legin · May 24, 2020

Standard there is no relay so you just have the tap switch. Its most likely you have a high resistance across the tap switch contacts due to arcing.

You should remove the tap switch and clean the contacts with abrasive paper, you can check before doing this to confirm its the switch by shorting across the terminals if you want.

The relay is a modification to transfer the switching current from tap switch to the bigger and tougher relay contacts to avoid this eventuality.

jliungman · May 24, 2020

Legin said:
Standard there is no relay so you just have the tap switch. Its most likely you have a high resistance across the tap switch contacts due to arcing.

You should remove the tap switch and clean the contacts with abrasive paper, you can check before doing this to confirm its the switch by shorting across the terminals if you want.

The relay is a modification to transfer the switching current from tap switch to the bigger and tougher relay contacts to avoid this eventuality.

This worked, thanks! Nice to not have to buy a new tap.
Adding a relay seems like a good idea!

Loz · May 24, 2020

mikeco11 · Sep 25, 2020

Loz said:
View attachment 59763

Hi, I tried this as a precaution after I fitted a new working tap. But I wasn't able to get the tap to work with the relay in place (in fact now I can't get the tap to work at all event though rewired back to normal). Please could you add the terminal numbers for the 4 or 5 way relay in the diagram, so I can be sure I got the right ones? Also, could you suggest how I can test I haven't blown a fuse or something (I can't find the right fuse to check anywhere!). thanks

Loz · Sep 25, 2020

If it doesn't work after reconnecting, then I expect the fuse has blown, it's an orange 5A one (there are 2, 1 for camper display the other for the pump)

I'll add the terminal numbers a bit later on.

Mr B · Jul 7, 2021

Loz said:
If it doesn't work after reconnecting, then I expect the fuse has blown, it's an orange 5A one (there are 2, 1 for camper display the other for the pump)

I'll add the terminal numbers a bit later on.

Hi Loz - what relay do I need? There are 7 different types here and I'm a bit confused?

I was going for a 30A 4 pin - is that correct?