Wiring Diagram for Heated grips through a relay

[salty_monk]

Anyone have one to hand? I have the Symtec grip heaters with 3 wires, no resistors (came higly recommended on here from CA Sport Touring) http://www.casporttouring.com/store/...and_cont_%2450

I haven't put a lot of time into it yet but I'm wondering if there is a way to get the relay to do the bulk of the switching work rather than running the full load through the switch. The switch that came with it is huge & I have picjed up a much smaller one from "the shack" DPDT Mini Toggle but it's only rated at 6A (125v) rather than 10A (125v). The switch is a 3 position for "hi / low".

The only obvious way I can think of involves using two relays....

Also can anyone tell me if this new switch will be man enough to switch the main circuits if I just push power from the relay direct to the switch? They have a max draw of 20w at 14v which doesn't seem like a lot to me....

Cheers,

Dan

[hikermikem]

hey dan,

look like you're getting ready to visit new england

[srsupertrap]

Don't have anwers to your relay question but I installed those grip heaters on a 92 ST1100 which has a superior charging system to a GS anything. With the heater switch "On" at idle the ST lights would dim and the rpm would also drop. Thought about installing them on the GS but decided better not . . . I don't have the DMM measurements to back up my point but I am inclined to think the GS charging system won't handle them for the long term if you run the heaters all the time

[posplayr]

Anyone have one to hand? I have the Symtec grip heaters with 3 wires, no resistors (came higly recommended on here from CA Sport Touring) http://www.casporttouring.com/store/...and_cont_%2450

I haven't put a lot of time into it yet but I'm wondering if there is a way to get the relay to do the bulk of the switching work rather than running the full load through the switch. The switch that came with it is huge & I have picjed up a much smaller one from "the shack" DPDT Mini Toggle but it's only rated at 6A (125v) rather than 10A (125v). The switch is a 3 position for "hi / low".

The only obvious way I can think of involves using two relays....

Also can anyone tell me if this new switch will be man enough to switch the main circuits if I just push power from the relay direct to the switch? They have a max draw of 20w at 14v which doesn't seem like a lot to me....

Cheers,

Dan

Dan
All I have to say is

V=IR and P=IV

20 Watts at 14v is only 20/14= 1.42 amps

So either switch would handle the current without a relay.

Getting ready for the cold winter?

Jim

[bwringer]

I've used those mini switches for the heated grips on both my shafties for three years. Never a problem, and no heat buildup.

In other words, find something else to worry about.

[bwringer]

Don't have anwers to your relay question but I installed those grip heaters on a 92 ST1100 which has a superior charging system to a GS anything. With the heater switch "On" at idle the ST lights would dim and the rpm would also drop. Thought about installing them on the GS but decided better not . . . I don't have the DMM measurements to back up my point but I am inclined to think the GS charging system won't handle them for the long term if you run the heaters all the time

Something is wrong with your setup, then.

I can tell you firsthand that a GS charging system is indeed perfectly adequate to run heated grips all the time.

The grips on all my bikes are supplied with power via a relayed circuit. I've never been able to see the slightest difference in headlight brightness with the grips on or off. (You can easily see a difference when the turn signals flash.)

The directions that come with the grips tell you to tap into a headlight or marker light circuit, which is just insane -- even on new bikes, the wiring for the lights is barely adequate for the headlight, let alone the added load of heated grips.

The nice thing about having a circuit switched by a relay is that you can use it to power other things if you wish. For instance, the air horn on my GS850 is powered by the same circuit (there's another relay to activate the horn). You could also use the same relay to power the coils.

[Redman]

....
....
Also can anyone tell me if this new switch will be man enough to switch the main circuits if I just push power from the relay direct to the switch? They have a max draw of 20w at 14v which doesn't seem like a lot to me....

Cheers,

Dan

Dan,

I will confirm what others are saying about electrical current draw, that 20watts at 14volts is 1.4 amps. And I image that 20 watts is at the high setting and low would be less, but that is only a guess, I have no familiarity with these heated grips. And is that the spec for one grip? or combined total for each?
Either way, that is well within the cabability of the switch.

I dont see a need for the relay between the switch and the heaters, as the switch has the capacity to handle the current draw of the heater(s).

THe GSes I know about have an extra fuse/terminal in the fuse block for such things, and is good to use that so dont effect any other circuit in event that a problem blows a fuse. But that fuse terminal is not switched on/off with the ignition switch, and that means you could leave the heated grips on when bike is off and drain the battery. I would suggest using a relay only to switch on/off the power to the hi/lo switch, and have the relay coil wired into maybe the signal circuit (org/grn) so it is switched on/off with the ignition switch.

Before someone could draw you a schematic, we would have to know what wires come from the heaters and which wires are what. CAn you identify each wire from the grip heater(s)?


********Found this on the webpage link you provided**************
- Fits under existing grips.
- This kit is specific for motorcycles and includes a toggle switch as well as commonly needed components for installation.
- Thousands of satisfied customers are using them.
- Current draw on high setting is 3 Amps at 13.5 Volts.

*************** end cut-n-paste****************************

It says current draw of 3 amps (and specifically states "on high setting"), which as about the 1.4 times 2 that we mentioned. So, switch you have should be okay (withoug gettting into discussion that theswitch rating is probalbly for AC and you are switching DC).

.

[posplayr]

Dan,


It says current draw of 3 amps (and specifically states "on high setting"), which as about the 1.4 times 2 that we mentioned. So, switch you have should be okay (withoug gettting into discussion that theswitch rating is probalbly for AC and you are switching DC).

.

We are now talking closer to 40 watts. Probably best to only put it on high when traveling down the road at higher RPM

[salty_monk]

Yes, 20 watts one side & 16 watts the other I think actually... I didn't have the packaging on hand when I posted last night.

I know the P=IV (I have some pysics qualification somewhere...) but it doesn't stretch to telling me if a switch rated at 6A at 125v ac will handle 3A at 12v DC...

Anyway.. from Brian's post it sounds like the switch will handle it without destroying the contacts on the 2nd switch on so I'll just wire as per the diagram in the instructions but pull the live from the relay rather than the bike's loom.

The grip heaters are for 2 reasons (despite our great weather out here).

1. I hate riding with thick winter gloves
2. I have bad circulation & get cold hands & feet really easy for some reason! (runs in my family along with bad joints. On my mum's side).

I also considered a vest but what I like about the grips is it's no extra effort, you can just flip a switch, no stopping, no pre-planning etc.

Regarding the bike's charging system this one has the FH012 Mosfet RR wired in direct to the battery so I am hoping that it will compensate for the grip heaters. I'll post back when I get it running.

Cheers,

Dan

[posplayr]

Yes, 20 watts one side & 16 watts the other I think actually... I didn't have the packaging on hand when I posted last night.

I know the P=IV (I have some pysics qualification somewhere...) but it doesn't stretch to telling me if a switch rated at 6A at 125v ac will handle 3A at 12v DC...

Anyway.. from Brian's post it sounds like the switch will handle it without destroying the contacts on the 2nd switch on so I'll just wire as per the diagram in the instructions but pull the live from the relay rather than the bike's loom.

The grip heaters are for 2 reasons (despite our great weather out here).

1. I hate riding with thick winter gloves
2. I have bad circulation & get cold hands & feet really easy for some reason! (runs in my family along with bad joints. On my mum's side).

I also considered a vest but what I like about the grips is it's no extra effort, you can just flip a switch, no stopping, no pre-planning etc.

Regarding the bike's charging system this one has the FH012 Mosfet RR wired in direct to the battery so I am hoping that it will compensate for the grip heaters. I'll post back when I get it running.

Cheers,

Dan

Dan,
I did not see in your original post that you raised an issue about using a switch with only an AC rating to switch DC (I don't think you asked that).

The switch that came with it is huge & I have picjed up a much smaller one from "the shack" DPDT Mini Toggle but it's only rated at 6A (125v) rather than 10A (125v). The switch is a 3 position for "hi / low".

I did a quick search and the answer to that question seems to be to go by the manufactures specification. If the manufacturer does not specify a DC voltage and current limits then you are kinda on your own.

You could guess and a good starting point seems to be derate down to 1/5 of the AC power to get a safe DC power.

Looking at your question above it is not clear if you are trying to replace a switch rated at 10A (125V) DC with a 6A 125V AC switch. It would probably work at least for a while till the contacts fail and you end up switch it out regularly. The other approach was your original to use it to switch a relay .

Jim

[salty_monk]

Sorry for confusion, it was late

Original is rated 10A 125v (no mention of AC or DC from memory). The new one is rated 6A 125v (again no mention of AC or DC).

I guess the voltage is the giveaway.. Seems to be the switch Brian is using & they are cheap so if it goes I'll replace it. As you say trial & error.

Not sure I can be bothered to wire in 2 relays (it has 2 circuits (heaters have 3 wires) for hi low so only way I can see being able to switch the relay is to switch 1 relay for each circuit.

Dan

[bwringer]

It'll be fine, really.

The biggest problem is how to solder the wires onto those teensy-tiny mini terminals on the back of that wee little switch. You need beady eyes, nerves of steel, and steady hands.

Here's a really crappy pic of the switch on my VX800 -- the switch on my GS850 is mounted the same way. It's a simple tab of stainless steel (crudely pounded flat and painted black) with a 1/4" hole at each end. You can sort of see that the switch body is covered with shrink tubing for a nice clean look and weather resistance.

[salty_monk]

Thanks! think I have room on my custom ignition \gauge plate on this one although your idea really puts it at hand so maybe I'll go with that.

[GS1000G Shopper]

Anyone have one to hand? I have the Symtec grip heaters with 3 wires, no resistors (came higly recommended on here from CA Sport Touring) http://www.casporttouring.com/store/...and_cont_%2450

I haven't put a lot of time into it yet but I'm wondering if there is a way to get the relay to do the bulk of the switching work rather than running the full load through the switch. The switch that came with it is huge & I have picked up a much smaller one from "the shack" DPDT Mini Toggle but it's only rated at 6A (125v) rather than 10A (125v). The switch is a 3 position for "hi / low".

The only obvious way I can think of involves using two relays....

Cheers,

Dan

Old thread, but occasionally someone runs across them and may need a diagram. Since there was not one posted I thought I'd help out. I had a two-speed fan relay setup in a V8 RX-7 that was very similar.. and very easy to modify the diagram. This uses a three position switch low/off/high.
Two automotive SPDT type relays:


Assumptions-
12 volts comes into the switch.
If off, it goes nowhere.
If low, high is not energized and it energizes the low relay coil and sends the load to the low input of the heater.
If high, low is not energized and it energizes the high relay coil and sends the load to the high input of the heater.

[salty_monk]

I actually wired them like this



BW is a ground. I actually picked up the orange wire in the rear light bundle as a switching wire from memory.

2nd relay wasn't necessary as the switch can handle even the high current fine.
For something more powerful a 2nd relay would protect the switch though. Good diagram.