The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Lucas, Ignition, Charging, Electrical => Topic started by: Peter Gee on 12.08. 2019 22:46

Title: On Pos Earth, Which Connections to Ammeter?
Post by: Peter Gee on 12.08. 2019 22:46

On a 59 SA7SS:

Hope this is not a daft  question but I don't understand  electrics as well as I do mechanics. . So the ammeter is marked on the face -/+ and has left/right corresponding connections, looked at from the connection side.

GIVEN : You have a  POS earth loom. You have Brown/Blue wires marked by the loom maker  for connection to  Battery -NEG and to be connected  to the ammeter,

Question  : Should these wires  be connected to the + POS side or - NEG side    of the ammeter, or does it not matter?

Thanks folks

from the only A7SS between Cairo and Capetown.

Title: Re: On Pos Earth, Which Connections to Ammeter?
Post by: trevinoz on 12.08. 2019 23:06

Just connect it so that the ammeter shows discharge when the lights are turned on and charge when the generator is on line.

Title: Re: On Pos Earth, Which Connections to Ammeter?
Post by: duTch on 12.08. 2019 23:08

 Off the top of my head, I'd suggest the the ammeter doesn't have polarity; blue one comes from 'A' on the regulator and if you connect them and turn a light on (no engine) and it shows discharge (-) switch is correct, but if the ammeter shows (+) they are wrong.

 trev rounded me up

Title: Re: On Pos Earth, Which Connections to Ammeter?
Post by: AdrianJ on 13.08. 2019 08:04

I put mine on the wrong way round and the ammeter showed charging when the lights were turned on without the engine running, so I just swapped them. It does no harm.
Adrian.