Pump switch

[Chris Joyce]

Just planning out my switches etc on the camper conversion.
Is it preferred practice to use a separate switch for the water pump or are the micro switch type taps ok?

I notice a lot of conversions and control panels have a separate switch

Thanks

 

[Spaghetti]

I prefer a cut off switch. I make sure I turn the power to the tap off if the tank is empty to prevent running the pump accidentally when it’s dry.

 

[Loz]

Just planning out my switches etc on the camper conversion.
Is it preferred practice to use a separate switch for the water pump or are the micro switch type taps ok?

I notice a lot of conversions and control panels have a separate switch

Thanks

You can use a microswitch as long as it controls a small relay that actually switches the pump otherwise the microswitch will eventually burn out its contacts.

 

[Chris Joyce]

Thanks guys.
Excuse my ignorance, will the microswitch that is built in to the tap not turn the pump on and off when it’s activated?

I think I’ll go down the route of a separate switch, having done some more reading it sounds as though the microswitch isn’t the best anyway

 

[boopzz]

Damn, I was under the assumption I could also just use the microswitch. Will have to delve into this a bit more. Any base line products that a lot of people use? Or just a case of buying a relay and wiring yourself?

 

[Spaghetti]

The micro switch does turn the tap on and off, but sometimes we use the van without filling the tank and my kids may try and use the sink when the power is on, and I don’t want them running the pump dry, so just isolate it.

 

[Spaghetti]

Damn, I was under the assumption I could also just use the microswitch. Will have to delve into this a bit more. Any base line products that a lot of people use? Or just a case of buying a relay and wiring yourself?

I don’t think mine has a relay on the pump. I’ll see how long it lasts. It’s about two years old at the moment.

 

[Ann3x]

If you use the microswitch directly it will work the pump just fine BUT the contacts on the microswitch are so small that they will burn out pretty fast with the pumps full current running through the switch.

You can either wire directly & replace the microswitch fairly often or fit a relay so that the microswitch is not receiving the bulk current & is protected.

 

[Burnstar]

The pump should be a water pressure activated one, i.e. it will self prime then shut off as long the pressure on the outlet side is high (i.e. the tap is closed) once you open the tap the pressure drops and the pump turns on. The tap in my camper is just an ordinary 'old fashioned' mixer tap.

The modern pumps won't get damaged easily, you'd have to run them dry for a while to cause damage. I also have a master switch that powers my accessories off (fridge, lights, pump)

 

[Loz]

The pump should be a water pressure activated one, i.e. it will self prime then shut off as long the pressure on the outlet side is high (i.e. the tap is closed) once you open the tap the pressure drops and the pump turns on. The tap in my camper is just an ordinary 'old fashioned' mixer tap.

The modern pumps won't get damaged easily, you'd have to run them dry for a while to cause damage. I also have a master switch that powers my accessories off (fridge, lights, pump)

I think the OP was referring to a small "whale" in-tank submersible as opposed to a sureflow or similar you describe.
I have used both and each has its own issues, the sureflow can be an issue if the pipe comes off, or the tap gets knocked on, for instance and empties your water tank into the van. (bitter experience here)

 

[Ann3x]

The pump should be a water pressure activated one, i.e. it will self prime then shut off as long the pressure on the outlet side is high (i.e. the tap is closed) once you open the tap the pressure drops and the pump turns on. The tap in my camper is just an ordinary 'old fashioned' mixer tap.

The modern pumps won't get damaged easily, you'd have to run them dry for a while to cause damage. I also have a master switch that powers my accessories off (fridge, lights, pump)

Depends on the pump being used. Submersible/booster types need a microswitch to operate. Pressure switched / diaphram type just need a normal tap, no switch, but also need more complex plumbing.

 

[Loz]

I don’t think mine has a relay on the pump. I’ll see how long it lasts. It’s about two years old at the moment.

No too difficult to wire in a relay, here is a mod I did for the California which has a microswitch and most are burnt out after 2 years.

 

[Spaghetti]

Yeah, I used to wire in relays for all the spot lights on my old cars many moons ago, but haven’t investigated this yet. By the sounds of things, I probably should! If I ever take the fridge out, I’ll fit a small 12v relay just to take the load off the switch.

 

[j4ckal]

No too difficult to wire in a relay, here is a mod I did for the California which has a microswitch and most are burnt out after 2 years.

View attachment 68695

I'm running a California pump and tap and have wired it directly with no switch. I was going to add one at some point but only for the reasons listed above (ie. running the tank dry/flooding the van).
So the microswitch in my tap may fail after a couple of years then?
The old smev unit in my T4 lasted for the 5 years or so I had it with no relay wired in, just a switch to isolate, are the Cali ones a known weak point?

@Loz where would be the best place for buying relays for this (and general wiring products), I will add one if needed and would like a way of switching the fridge and temp controller off also, I'm guessing a relay would be best for this too?

 

[Loz]

I'm running a California pump and tap and have wired it directly with no switch. I was going to add one at some point but only for the reasons listed above (ie. running the tank dry/flooding the van).
So the microswitch in my tap may fail after a couple of years then?
The old smev unit in my T4 lasted for the 5 years or so I had it with no relay wired in, just a switch to isolate, are the Cali ones a known weak point?

@Loz where would be the best place for buying relays for this (and general wiring products), I will add one if needed and would like a way of switching the fridge and temp controller off also, I'm guessing a relay would be best for this too?

Yes, a weakness on the Cali, some are lucky and it gets replaced under warranty, but as always it depends on how much it is used.

Vehicle Wiring Products Ltd Suppliers of Auto Electrical Parts for parts, but the relay is nothing special, just the smallest one I could get.

 

[Ann3x]

The old smev unit in my T4 lasted for the 5 years or so I had it with no relay wired in, just a switch to isolate, are the Cali ones a known weak point?

Was your smev microswitched?
From what I've heard not just a cali specific issue but common to most microswitched taps. In any case, it wont hurt to use the relay approach.

 

[j4ckal]

Was your smev microswitched?
From what I've heard not just a cali specific issue but common to most microswitched taps. In any case, it wont hurt to use the relay approach.

Yes just the standard microswitched tap, didn't realise there was an issue with them. I just assumed the current draw was so low on those little in-tank pumps a relay wouldn't be needed. Yes I'll definitely be putting a relay on it and I think on a couple of other circuits I've wired up whilst I'm at it, and possibly relocate the fuse box, more work

 

[Ann3x]

Yes just the standard microswitched tap, didn't realise there was an issue with them. I just assumed the current draw was so low on those little in-tank pumps a relay wouldn't be needed. Yes I'll definitely be putting a relay on it and I think on a couple of other circuits I've wired up whilst I'm at it, and possibly relocate the fuse box, more work

Always more work!

 

[Tim Sparkes]

I just remove the fuse when the water tank is empty.

 

[marchugo]

No too difficult to wire in a relay, here is a mod I did for the California which has a microswitch and most are burnt out after 2 years.

View attachment 68695

Hi Loz,

Thank you for this drawing I found here, while searching for a solution for my burnt out microswitch in the Cali tap.

But: I have always thought that the microswitch in the tap is only switching/interrupting the Minus (-) cable. Seeing your scheme now, it looks like that the two wires that go into the microswitch in the tap, are a Plus AND a Minus?

Is my impression correct, and are both Plus and Minus from the cable connectors under the sink going straight into the microswitch? Or is it only the Minus wire from this connector, that goes into the microswitch?

I hope to understand this right, because at the moment I don't know exactly how to wire in the relais. In other words: which wire should I use to trigger the relay, and where do I connect it to on this relay?

Regards from Amsterdam,

Marc.