Ammeter wiring.

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jddevel
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Ammeter wiring.

Post by jddevel » Fri May 05, 2023 2:32 am

For clarification. Does the wiring diagram as shown in the manual indicate the wiring as viewed from the front or as viewed from the back. Why I ask is because I think I`ve installed part of my new loom the wrong way round. Although I show the car charging at the battery (I`m still positive earth) my ammeter is showing a negative. As viewed from the BACK I`ve my brown and white wire going to the LEFT terminal and then on to "A" at the control box and the RIGHT terminal (Brown wire) going to the starter motor. SO I think I`ve wired it up in reverse.
SECOND question. The reading at around 2000 rpm AT THE BATTERY is showing around 15volts. Seems potentially a bit high. Comments please.

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Steve Simmons
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Re: Ammeter wiring.

Post by Steve Simmons » Fri May 05, 2023 8:23 am

Make sure the battery is fully charged and check again. If I'm remembering correctly the reading should be around 13.5 volts, measured at around 2500 RPM.

The diagram does show the dash from the rear (note speedo is no the right of the diagram). If looking at the ammeter from the REAR then the brown/white wire goes on the right, and then on to the A terminal.
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jddevel
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Re: Ammeter wiring.

Post by jddevel » Fri May 05, 2023 9:21 am

As I suspected Steve, I`ve got them round the wrong way!!!!! Hence the reading is showing a discharge when it is in fact charging. Regarding the battery charge it`s showing just over 12.5 so might be a bit low. Regarding the high voltage shown at around 2000 (I`m not obviously at the car at the moment so would need to check at 2500) if indeed it continues to show around 15 volts would this be considered to be high once the battery is up to around 13+? If so would this indicate a faulty control box?

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Rob Reilly
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Re: Ammeter wiring.

Post by Rob Reilly » Fri May 05, 2023 11:49 am

Yes, the wiring diagrams seem to be all drawn from the back, as you would view the panel on your workbench, wiring it up.
I have 2 ammeters dated 4/37 and 6/51 and neither has any labeling of the terminals A or B.
So do we assume A is near the speedo and B is nearer the driver?
1937 TA 1271

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jddevel
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Re: Ammeter wiring.

Post by jddevel » Sat May 06, 2023 4:15 am

Reversed the wires and all now appears good. Howver on checking everything else out horn not working. Couldn't find the fault except 35 amp fuse blown. Must be a reason!!!!!

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