Sizing Wires for Gauges

[Clatter]

So I got me three of those new ISP gauges here..

Based upon past experience, it always seems hard to get lights the same brightness.

Speedo and gas gauge are all dim, and the aftermarket gauges are really bright.

And that got me to thinking about sizing wires..

Here we have three gauges in their little bracket,
And how I -planned- on wiring up the grounds.

Stopped after putting a couple ends on,
Because I started feeling like I was under-sizing the wire.
(Pretty cool you can crimp three wires in one end with these new crimpers ).

Using some brown ground wire from an old harness,
The wire ends up being what the diagram lists as a 0,5 size - a.k.a. 20AWG.

Didn't put the ends on yet,
But,
Notice that both the light bulbs _and_ the gauges themselves need a ground wire.
Was planning on just 'hopping' over and making one harness up for all grounds
(Remember, I haven't put the ends on at the bulb holders yet they're just tucked up there).

So,
Am I signing myself up for some wonky gauge readings and dim bulbs?

Thinking of how they use these big steel buss bars for grounds..
Don't the grounds need to be a bigger gauge?



Making up the light wires,
Using a bit of old harness,
Funny how they have sideways stripes, long-ways, and spiral,
All in the same harness!

Anyways,
Input from out electrical gurus here is much appreciated.

Stoked to be taking my wiring up a notch..
_________________
Bus Motor Build

What’s That Noise?!?

[Wildthings]

Your current draw is pretty tiny, I would think that 20 AWG would work fine. If your aftermarket gauges are too bright when you have dimmed the rest of the dash lights you could add a resister in series with them assuming the gauges have incandescent bulbs.

[busdaddy]

[Wildthings]

Again assuming you have incandescent bulbs you could just buy lower wattage bulbs, there are many different wattages out there.

[kreemoweet]

Stock bus instrument/gauge bulbs are 1.2 watts. Aftermarket stuff is frequently something like 5 watt.
WAY too bright IMO. The little 1.2 bulbs were even on a circuit with a dimmer.
_________________
'67 bug: seized by the authorities
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[SGKent]

I had the same issue with some VDO gauges. Telford created a trimming circuit that I built. It allows me to trim the non-factory gauges to the rest of the cluster so they all match. Once trimmed they all go up and down together at the same brightness.

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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Clatter]

Thanks for the help gentlemen.

Unfortunately it’ll be a while before i get to see how it works.

Looks factory, though, eh?

Love my new crimper and ends.

Even if it has a bit of trouble doing two or three wires at once..
The strain relief part that crimps the insulation doesn’t really bite,
But it sure smooshes the tar out of out of the copper wire.

_________________
Bus Motor Build

What’s That Noise?!?

[NASkeet]

[Clatter]

https://www.vwispwest.com/DepartmentsTYPE3-ACCESSORIESISP-GAUGES
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Bus Motor Build

What’s That Noise?!?

[NASkeet]

[telford dorr]

Looks good so far. I'd recommend adding some 1 inch lengths of 1/4 inch shrink tubing on all terminals (except maybe ground). Will prevent arcs and sparks in the future.

Adding resistance in series with the aux gauge lights will make them the same brightness as the normal dash lights (experiment - maybe 18 ohms, 2 watt).
_________________
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