Frying Tonight!

[Dark61]

Following some excitement with a melting wire from the starter to the ammeter, I’ve taken an interest in all things wire. Can anyone tell me please from the attached what SW and CB stand for with regard to the coil? Is this code for - and +? Also for the 57 88” , were indicators at the front only? Mine has indicators at the front single stop light only on passenger rear and a combined “modern” lens drivers side rear containing stop light and flasher light . All comments gratefully received as usual. Trucks not on the road so no rush.
cheers,

d

[Tombie]

Switch SW
Contact Block CB

[mick88]

Following some excitement with a melting wire from the starter to the ammeter, I’ve taken an interest in all things wire. Can anyone tell me please from the attached what SW and CB stand for with regard to the coil? Is this code for - and +? Also for the 57 88” , were indicators at the front only? Mine has indicators at the front single stop light only on passenger rear and a combined “modern” lens drivers side rear containing stop light and flasher light . All comments gratefully received as usual. Trucks not on the road so no rush.
cheers,

d

Dark,
are you running a genny or an alternator?
If running an alternator it's a good idea to bypass the ammeter as they can be prone to overheating/damage/fire when the system has been upgraded to an alternator, especially a higher output unit.

Cheers, Mick.

[OneOff]

Dark,
are you running a genny or an alternator?
If running an alternator it's a good idea to bypass the ammeter as they can be prone to overheating/damage/fire when the system has been upgraded to an alternator, especially a higher output unit.

Cheers, Mick.
Well that’s a worry...

More information on that please? I have a higher output alternator fitted to mine...

[JDNSW]

The maximum current expected to flow through the ammeter (and associated wiring) in a Series 1 is around 30A. The smallest alternator is likely to be rated at 35A, with most higher than this.

The result of this will be current beyond the design level for both the ammeter and wiring. Unless the alternator is rated at something like 60A or higher, this current will be unlikely to melt the wiring if it is in good condition - but it may not be. this sort of current, especially the sudden rush just after starting, is likely to damage the ammeter by bending the pointer.

Also, the thin wiring to and from the ammeter is going to limit the actual charge from the alternator.

The best solution is to bypass the ammeter, running a wire direct from the alternator to the battery - in this case, the ammeter will only show the discharge, and adding a voltmeter to show the battery state could be a good idea.

[LR1953]

The maximum current expected to flow through the ammeter (and associated wiring) in a Series 1 is around 30A. The smallest alternator is likely to be rated at 35A, with most higher than this.

The result of this will be current beyond the design level for both the ammeter and wiring. Unless the alternator is rated at something like 60A or higher, this current will be unlikely to melt the wiring if it is in good condition - but it may not be. this sort of current, especially the sudden rush just after starting, is likely to damage the ammeter by bending the pointer.

Also, the thin wiring to and from the ammeter is going to limit the actual charge from the alternator.

The best solution is to bypass the ammeter, running a wire direct from the alternator to the battery - in this case, the ammeter will only show the discharge, and adding a voltmeter to show the battery state could be a good idea.

An alternative to John's solution above would be to install a "shunt" across the ammeter terminals and modify the ammeter to suit, and upgrade the wiring in the circuit to carry the higher currents safely and efficiently as John has suggested,

Cheers, Rob S

[Rick Fischer]

Was also going to suggest a "shunt" to say 50%, then it is just double the displayed value.

You will need someone who can calculate the value of the resistor in parallel that you will need to achieve that result. (across the two ammeter terminals).

Cheers

RF