+- Austinsevenfriends (https://www.austinsevenfriends.co.uk/forum)
+-- Forum: Austin Seven Friends Forum (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=1)
+--- Forum: Forum chat... (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=14)
+--- Thread: Ignition lamp resistor (/showthread.php?tid=692)
Ignition lamp resistor - Robert Leigh - 15-01-2018
Please can someone advise the resistance value of the wire wound resistor used for ignition lights. I assume that this would be the same on the SM5 round switch panel as it is on the later ignition lamp fitted to late RNs onward. I have previously shorted the resistor position and used a 12v mes instrument lighting lamp (lowest wattage I could find), which is very satisfactory, but I want to advise a purist.
Robert Leigh
RE: Ignition lamp resistor - Bill Dixon - 15-01-2018
On my RP I used a 27ohm 0.6watt resistor , the lamp is a 2.5 volt 0.2 amp on a 6 volt system. the current rating is important. This should work on the RN switch panel. This mod has worked for me since 1971. If using 12 volt system try a 47 ohm resistor. As far as I can tell Lucas used the 2.5 0.2 lamp as no 6volt or 12 volt lamps were made in the 1930s.of the correct current rating.
RE: Ignition lamp resistor - Tony Press - 15-01-2018
(15-01-2018, 06:04 PM)Bill Dixon Wrote: On my RP I used a 27ohm 0.6watt resistor , the lamp is a 2.5 volt 0.2 amp on a 6 volt system. the current rating is important. This should work on the RN switch panel. This mod has worked for me since 1971. If using 12 volt system try a 47 ohm resistor. As far as I can tell Lucas used the 2.5 0.2 lamp as no 6volt or 12 volt lamps were made in the 1930s.of the correct current rating.
My Lucas SM5 panels are fitted with 6 volt 3 watt MES ignition lamps.
Cheers, Tony.