08-04-2021, 09:33 PM
(This post was last modified: 10-04-2021, 08:36 AM by Colin Morgan.)
Okay - it is not you - when I come to look at the set-up for ARQ and ARR Rubies, it doesn't appear to use the full capability of the Lucas PLC and CFR2 combination.
There is information on the use of the CFR2 and PLC switch in the Vintage Alvis Manual. This shows a CFR2 cut-out fully wired up with an extra wire that is not on the Seven diagram that goes from F1 on the switch to F1 on the CFR2 cut-out - and there is no direct connection shown between F1 and F2 as on the Austin 7 diagrams, both official Austin and John Cornforth's.
'ALVIS' SET-UP
The workings of a FULLY WIRED up CFR2 are explained in the Alvis manual for the four positions as follows:
Summer or Half Charge Position
The resistances R1 and R2 are in series with the dynamo field to limit the charging rate. (D connects through the resistances to F2, nothing else is connected inside the switch.)
Winter Charge Position
R2 is shorted out by the contacts bridging between terminals D and F1 in the switch. (This reduces the resistance in the field circuit so increases dynamo output from the previous setting.)
Side and Tail
Moving the switch again does not affect the charging circuit, but connects the side and tail lights the battery via terminal A. (Terminal A is connected directly back to the battery, and back through to the dynamo via the electromagnetic switch in the cut-out.)
Head
In this position both R1 and R2 are shorted out by the switch bridging between terminals D and F2. This gives maximum field current and output. In this position the field fuse is no longer in circuit.
So that is the full set-up for a CFR2 switch and PLC switch. It offers three levels of charging using R1+R2, R1 only, and no extra resistances in the field coil circuit respectively. (The charging rate is the same for Winter charge and Winter charge with side and tail lights on.)
AUSTIN RUBY SET-UP
However, the Austin set-up is simpler. There is only a low charging rate on Summer/Half/Low and a single higher charging rate for the other three switch positions - namely, 'Winter/High', 'Side/Tail' and 'Head'. This seems to be set up as follows:
As mentioned above, on the ARQ/ARR Ruby there is no wire between F1 on the switch and F1 on the cut-out. Both F1 and F2 on the switch (where they are connected together) go to F2 on the cut-out. The cut-out has no wires from F1, therefore, the terminal that splits the two resistances in the cut-out is not being used so they cannot be being used separately.
In the Summer/Low/Half setting, the switch does not include the D terminal so there is no connection on the switch between D and the combined F1 and F2. The field circuit coming from the dynamo via D resistance includes two resistances R1 and R2 on the way to F2 so the charging rate is as low as it can be.
Once the switch is moved to the Winter/High position, switch terminal D is connected to switch terminal F1 and F2 which connects D directly to cut-out F2 which short-circuits both resistances R1 and R2. The resistance in the field circuit is a low as it can be so the charging rate is as high as it can be - so there is no intermediate charge rate.
Moving the switch to the Side/Tail position does not change the charging circuitry - switch D and F1/F2 remain connected to cut-out F2.
Moving the switch to the Head position connects switch D to switch F2, which does not change the charge rate as both resistances remain bypassed.
Therefore, the Seven appears to have two charging rates - Summer/Low/Half and Winter/High - this higher rate is retained when the switch is in both of the lighting positions. (As the field fuse is in series with the two resistances, it is eliminated from the circuit for all settings except Summer/Low/Half.)
There is information on the use of the CFR2 and PLC switch in the Vintage Alvis Manual. This shows a CFR2 cut-out fully wired up with an extra wire that is not on the Seven diagram that goes from F1 on the switch to F1 on the CFR2 cut-out - and there is no direct connection shown between F1 and F2 as on the Austin 7 diagrams, both official Austin and John Cornforth's.
'ALVIS' SET-UP
The workings of a FULLY WIRED up CFR2 are explained in the Alvis manual for the four positions as follows:
Summer or Half Charge Position
The resistances R1 and R2 are in series with the dynamo field to limit the charging rate. (D connects through the resistances to F2, nothing else is connected inside the switch.)
Winter Charge Position
R2 is shorted out by the contacts bridging between terminals D and F1 in the switch. (This reduces the resistance in the field circuit so increases dynamo output from the previous setting.)
Side and Tail
Moving the switch again does not affect the charging circuit, but connects the side and tail lights the battery via terminal A. (Terminal A is connected directly back to the battery, and back through to the dynamo via the electromagnetic switch in the cut-out.)
Head
In this position both R1 and R2 are shorted out by the switch bridging between terminals D and F2. This gives maximum field current and output. In this position the field fuse is no longer in circuit.
So that is the full set-up for a CFR2 switch and PLC switch. It offers three levels of charging using R1+R2, R1 only, and no extra resistances in the field coil circuit respectively. (The charging rate is the same for Winter charge and Winter charge with side and tail lights on.)
AUSTIN RUBY SET-UP
However, the Austin set-up is simpler. There is only a low charging rate on Summer/Half/Low and a single higher charging rate for the other three switch positions - namely, 'Winter/High', 'Side/Tail' and 'Head'. This seems to be set up as follows:
As mentioned above, on the ARQ/ARR Ruby there is no wire between F1 on the switch and F1 on the cut-out. Both F1 and F2 on the switch (where they are connected together) go to F2 on the cut-out. The cut-out has no wires from F1, therefore, the terminal that splits the two resistances in the cut-out is not being used so they cannot be being used separately.
In the Summer/Low/Half setting, the switch does not include the D terminal so there is no connection on the switch between D and the combined F1 and F2. The field circuit coming from the dynamo via D resistance includes two resistances R1 and R2 on the way to F2 so the charging rate is as low as it can be.
Once the switch is moved to the Winter/High position, switch terminal D is connected to switch terminal F1 and F2 which connects D directly to cut-out F2 which short-circuits both resistances R1 and R2. The resistance in the field circuit is a low as it can be so the charging rate is as high as it can be - so there is no intermediate charge rate.
Moving the switch to the Side/Tail position does not change the charging circuitry - switch D and F1/F2 remain connected to cut-out F2.
Moving the switch to the Head position connects switch D to switch F2, which does not change the charge rate as both resistances remain bypassed.
Therefore, the Seven appears to have two charging rates - Summer/Low/Half and Winter/High - this higher rate is retained when the switch is in both of the lighting positions. (As the field fuse is in series with the two resistances, it is eliminated from the circuit for all settings except Summer/Low/Half.)