OE momentary SPDT switch for puma?

I've sought some clarification from the manufacturer (blue sea systems) regarding the operating current draw of the 7713 model in the OFF state, using it with a SPST siwtch.

I'm chasing opinions from those of us on the right side of the pond ;-)

The 7713 is an auto releasing 'normally open' relay coil - my understanding is that this defaults to OFF when unpowered (open circuit).

I asked what operating current I could expect when using a SPST switch with this relay - answer back was 8mA, as per their specs:
https://www.aulro.com/afvb/images/im...015/03/720.jpg

...but this doesn't add up for me. I would expect 8mA when using a SPDT switch, as the relay would need to maintain a circuit to hold the coil OPEN or CLOSED...

My understanding was that if I'm using an auto releasing normally closed coil, with a SPST switch to pull the relay in and CLOSE (complete) the circuit, the helper spring in the relay will keep the circuit open without a current draw when no power is applied to the relay.
Is this right, or was I given a bum steer (or question misinterpreted)?

https://www.aulro.com/afvb/images/im...015/03/718.jpg

...And looking at the wiring diagram, it seems to support that the relay helper spring is what is holding the circuit OPEN, and that the only power input is that which is needed to power the coil and pull the relay contacts together to CLOSE the circuit.
Unless it's normal for a large relay/contactor such as this to use an internal powered coil to assist the helper spring to be normally open? :confused:


Another hint found in the bowels of the user manual is that a SPST switch, if used, may cause inadvertant switching if the terminals get damp. Surely that's not possible in a land rover?! :p

My guess (totally a guess) is that the 8mA is drawn from then main battery input terminal by some internal circuitry, doing who knows what. It obviously cant be drawn from the control input as it is open circuit.

This leakage also concerns me, as I am considering using this also. But perhaps the solution is to put a simple, cheap full load isolator on the supply side of this, and leave this isolator open for daily driving, and close it only when the winch might be required. That way there is no power supply to supply the leakage current during daily driving.

If you work out more, please let us know.

Mark

That's what confuses me.
ML-RBS Model 7713 is a new and improved version, but when you look into it, the only real benefit is slightly simpler wiring and the ability to run a SPST switch (which admittedly can lead to latching issues if moisture is present at the switch). How's that for marketing trying to 'value add' :p
I'm starting to see the 7713 model as a downgrade.

I know 8mA is not a deal breaker, but you add up a lot of accessories which draw a little bit, and before you know it you're depleting battery life while the car is unused. This is a compounded issue if were used in a boat that might see some action once a month.

ML-RBS Model 7700 is bi-stable. So the relay coil magnetically latches in one position or the other, and uses no power in either open or closed states. The current needed to switch is the same though by the looks, which is done by a momentary push button switch (DPDT- one switch switches 2 circuits - one to open, one to close the high current side of the RBS).

Quote:

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Originally Posted by Toxic_Avenger

That's what confuses me.
ML-RBS Model 7713 is a new and improved version, but when you look into it, the only real benefit is slightly simpler wiring and the ability to run a SPST switch (which admittedly can lead to latching issues if moisture is present at the switch). How's that for marketing trying to 'value add' :p
I'm starting to see the 7713 model as a downgrade.

I know 8mA is not a deal breaker, but you add up a lot of accessories which draw a little bit, and before you know it you're depleting battery life while the car is unused. This is a compounded issue if were used in a boat that might see some action once a month.

ML-RBS Model 7700 is bi-stable. So the relay coil magnetically latches in one position or the other, and uses no power in either open or closed states. The current needed to switch is the same though by the looks, which is done by a momentary push button switch (DPDT- one switch switches 2 circuits - one to open, one to close the high current side of the RBS).

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FYI I've had this set up on my truck for two or three years and the 8/1000A current draw is a complete non issue - my batteries were still fully charged after around 4 months without starting.

Are these the type of switches your talking about.

https://www.lrdirect.com/YUG000530LN...Rear-Fog-Lamp/

If so I have some I purchased in error.

Quote:

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Originally Posted by n plus one

FYI I've had this set up on my truck for two or three years and the 8/1000A current draw is a complete non issue - my batteries were still fully charged after around 4 months without starting.

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Have you got any pics of your setup?
What kind of switch are you using (Normal or Momentary SPST switch, or SPDT?)