angelfj Posted April 25, 2013 Report Share Posted April 25, 2013 Has anyone added up or better yet measured the total connected electrical load for a typical sidescreen TR ? Actually I was curious how Triumph decided which Lucas dynamo to fit to these cars. I discovered recently that the C39 dynamo (18 amps?) may not survive very long with sustained use of heater, wipers, main beams, and certain safety enhancements. Considering the modest capacity of these dynamos does anyone know if a heavy duty dynamo was offered. I find it hard to believe that the works cars, in particular the rally cars could ever function with the limited capacity of a C39 or C40. Cheer,s Frank Quote Link to post Share on other sites
Ashley James Posted April 25, 2013 Report Share Posted April 25, 2013 Watts = Volts x Amps and Amps = Volts divided by resistance (Ohms) Ash Quote Link to post Share on other sites
AlanT Posted April 25, 2013 Report Share Posted April 25, 2013 Measurements taken recently, with the proper Mk8 Avo meter shown in the WSM. Actually on a 4A. Dont think a sidescreen will be much different. Main Beam 10 surge 30A?Dip Head 8 dittoSide lights 1.5 Stop lights 3 Flashers 1.8 Horn 8.5 Start solenoid 4.5 Wiper 3 slow-speed Back in the 60's most UK cars had these dynamos we all knew that lights, heater fan, wipers would most likely take you into a battery discharge condition. This is in fact why the cars were fitted with ammeters. You were meant to trim the load to keep the battery charging. We also knew that the charging regulation would allow the battery to be damaged if it was flat. So if you took a jump start to get going you would put the headlights on to get the current down. I still do this actually because my modern car does not display current of course. I have a dim memory that typical rally cars were fitted with two dynamos. Quote Link to post Share on other sites
angelfj Posted April 25, 2013 Author Report Share Posted April 25, 2013 Measurements taken recently, with the proper Mk8 Avo meter shown in the WSM. Actually on a 4A. Dont think a sidescreen will be much different. Main Beam 10 surge 30A? Dip Head 8 ditto Side lights 1.5 Stop lights 3 Flashers 1.8 Horn 8.5 Start solenoid 4.5 Wiper 3 slow-speed Back in the 60's most UK cars had these dynamos we all knew that lights, heater fan, wipers would most likely take you into a battery discharge condition. This is in fact why the cars were fitted with ammeters. You were meant to trim the load to keep the battery charging. We also knew that the charging regulation would allow the battery to be damaged if it was flat. So if you took a jump start to get going you would put the headlights on to get the current down. I still do this actually because my modern car does not display current of course. I have a dim memory that typical rally cars were fitted with two dynamos. Many thanks Alan. Gee, they must have needed a shoe horn to get the second dynamo in! Quote Link to post Share on other sites
Alec Pringle Posted April 26, 2013 Report Share Posted April 26, 2013 Heater ? Frank, it's a sidescreen car. Miss Whiplash on wheels. Unadulterated masochism. You don't do surplus weight, so you don't need the heater, Chuck out the carpets and you won't feel the cold, but you will have lost more weight.. If you're still not warm enough, slot in a V8. No substitute for cubic inches. Rover V8 is lighter than a wet liner 4, more weight lost. Of course if you're a total wimp, Lucas did do bigger dynamos, up to all of 35amps, but you might need to swap out the voltage regulator for, say, a RB340 unit. Cheers Alec Quote Link to post Share on other sites
Nigel Lay Posted April 26, 2013 Report Share Posted April 26, 2013 (edited) C40 dynamo - max output 22amps RB106 regulator C45 dynamo - max output 25 amps C42 dynamo - max output 30 amps Both of the above as Alec say's use the RB340 regulator also the mounting brackets 'may' have to be altered slightly to fit them. Under running conditions with lights, wipers and heater (sorry Alec but it keeps Patsy's legs warm) our car draws about 18 amps. In practice have never had problems but probably never run for more than a couple of hours with everything switched on. I have a C40 dynamo. Nigel (with TS952) Edited April 26, 2013 by Nigel Lay Quote Link to post Share on other sites
ianc Posted April 26, 2013 Report Share Posted April 26, 2013 When I acquired 4VC in 1969, it was equipped with an RB340 regulator and what I was told was a high output dynamo. And looking at the photo of Kastner with one of the other cars just prior to the Shell 4000 Rally (1964), one can see the RB340. I can't say which of the likely dynamos listed by Nigel (C45 or C42) was fitted, because I never looked that closely at it, and an alternator was fitted when the car was re-built in the early 1990s. The mounting bracket seemed perfectly standard to me (and I had been running a TR2 for 6 years prior to acquiring 4VC). I cannot say whether Richardson fitted uprated dynamos to the sidescreen Works' rally cars. My hunch would be not - we used to watch the ammeter and minimise electrical consumption as much as possible! I can remember driving from Stafford to Esher in my TR2 without the dynamo charging - just sidelights as it got dark! Ian Cornish Quote Link to post Share on other sites
BlueTR3A-5EKT Posted April 26, 2013 Report Share Posted April 26, 2013 (edited) I drove the Moss TR 3 from Santa Barbara via Barstow to Lake Havasu without a charging system one evening. About 300 miles i suspect. The dynamo packed up as we drove to a Triumph Meet about an hour into the journey. I drove on in the twilight across the Mojave desert arriving near 11pm. The desert is surprisingly light at night until some monster truck blinds you with it's headlights, and all your night vision is impaired. Turned on side lights only when things came towards me or at built up areas where the plod may have lurked. A replacement dynamo arrived the next day and I was the impromptu technical entertainment fitting it. That one failed on me 2 weeks later on a ride and drive rally in Topanga Canyon... Moss changed their dynamo supplier that week and froze their stock. Cheers Peter W PS fit an alternator if you are intending to use the car in a modern way, using headlamps all the time, wipers, and of course the heater and overdrive. Edited April 26, 2013 by BlueTR3A-5EKT Quote Link to post Share on other sites
Malcolm Tatton Posted April 26, 2013 Report Share Posted April 26, 2013 Not a TR story but whilst the TR4 was the second car that I bought, the first was an Austin 7 special bought from Barking when I was a student in London. Twin SUs, shallow sump, electric fan, it had all the trick bits. Decided to bring it home to Stoke and had to bump start it because the battery had gone flat in the one week that it had been standing. I'm sure we rigged up a 6v ever ready battery to power the ignition on the basis that the main battery would begin to charge once we got going (and so it did). All went well until it got dark, headlights on a 6v car were like candles anyway, but in my youthful ignorance I had switched on the electric fan at the start of the trip and never switched it off (didn't realise then that It was only needed in traffic). So gradually the battery discharged, indicators got slower, lights got dimmer, and we finally came to a stop about 10 miles from home. Dad picked us up, we took the battery home and recharged it and went back next day to start the car and drive the rest of the way home! What still amazes me is how far we got, still got the car, another retirement project! Malcolm Quote Link to post Share on other sites
Guest Posted April 26, 2013 Report Share Posted April 26, 2013 I remember my dad installing a Smiths heater - the silver-ish wires- on the rear window of his Austin Landcrab (called 'Balanza' overhere in Holland). From that moment on, the charging light started to come on every time he switched on that heater. It would only dim when revving the enigine! Must have been one of the same dynamos. Menno (btw, I have fond memories of that car - and it was a nice feeling when I was able to sit in the back of one of these cars a few years back; brought back memories) Quote Link to post Share on other sites
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