help! relay wire leisure bat-alternator

[staffy31]

can anyone tell me how to join them relay wires from leisure battery to alternator please

[ake]

On what van?

[transit120mick]

Like this.





Mick

[staffy31]

me transit ex bt van now staffy camper av started it agen doing the laggin now carpets ready to stick on the morra but stil need to do me battery work i got one of them numark batterys from go outdoors av put that behind the seat inside a box but i havent wired it up yet so i got one of them relay wires that goes to the alternator

[redvendave]

a basic relay isnt a good idea , they burn out easily , i tried this route 100 amp relay ,100amp maxi fuses , relay lasted our 2weeks holiday ok when we next went away following weekend it just died .haveing looked into further its reckoned its relay chatter , as the relay is on and of all the time you stop and start engine . i have since fitted a intelligent relay , durite one £26 of ebay , this cuts in at out at set voltages, so is not constantly on and of everytime engine starts and stops , i have since had no problems , also use plenty of fuses to protect everything ,big enough for alternator output and leisure battery , and cables big enough etc

[mjsroofing]

I use a smart/intelegent relay in my van I run a few 12v items and a 1500w inverter with no problems.

[pepper]

I use the 200amp version (about £80 off ebay in mine) but I have a 3100w inverter!

[mjsroofing]

I use the 200amp version (about £80 off ebay in mine) but I have a 3100w inverter!

Think is around 80amp, 200amp is a lot but u can't have to much I suppose.

There is a way to calculate how much amp u need to wattage and volts but I don't remember.

[andycaca]

i think its as simple as watts/volt = amp

so 100w / 12v = 8amp

[mjsroofing]

i think its as simple as watts/volt = amp

so 100w / 12v = 8amp

Nice one

[ake]

i think its as simple as watts/volt = amp

so 100w / 12v = 8amp

Correct

Power (Watts) = Volts x Amps

[ajpmsport]

If you put it into a "power triangle" all you need is two parts of the equation. Just cover over the part you need to find out.

Power(watts)
_______________

Volts x Amps


100
__________ = 8.3 Amps

12
It works every way round, just cover over the part you are trying to find.

[andycaca]

in related news, i fitted one of those smart voltage sensing relays at the weekend. very nice and tidy install with no need to go under the bonnet
i chose the lazy option and bought a kit but the only really special bit is the relay. everything else is just fuses and cable
the relay on its own costs about 30 quid where i have seen it online

http://www.ebay.co.uk/itm/321037185762? ... 1439.l2649
Professional Smart Split Charge 70 Amp Kit

[knighty1981]

a basic relay isnt a good idea , they burn out easily , i tried this route 100 amp relay ,100amp maxi fuses , relay lasted our 2weeks holiday ok when we next went away following weekend it just died .haveing looked into further its reckoned its relay chatter , as the relay is on and of all the time you stop and start engine

that's nothing compared to all the other relays in the van... lights, horn, heater, starter, et. etc.etc..

sounds like you were just unlucky... I've done it that way loads of times and never had a problem

[mjsroofing]

a basic relay isnt a good idea , they burn out easily , i tried this route 100 amp relay ,100amp maxi fuses , relay lasted our 2weeks holiday ok when we next went away following weekend it just died .haveing looked into further its reckoned its relay chatter , as the relay is on and of all the time you stop and start engine

that's nothing compared to all the other relays in the van... lights, horn, heater, starter, et. etc.etc..

sounds like you were just unlucky... I've done it that way loads of times and never had a problem

I can second this I have done a few set ups with standard and smart relays, all around 70-80amp.

Never had a problem , but I was told that it is important that u have the live feed in the right side same with the trigger live too.
But yeah wiper relays, indicators etc they are turning on and off all the time, heater plug relay etc etc.

Just make sure u have a good quality relay not a cheap one.