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I have an alternator in my 3 so I installed a voltmeter. It seems to me that the headlights sure draw a lot of current when in use.Is this normal? If I was to have the heater on at the same time would that not be a lot of drain on the battery? Is there an upgrade to the charging system?
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TR2/3/3A Headlights and their extreme current draw?
- Thread starter karls59tr
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You can go for a bigger alternator Karl. My UK perspective-
The original dynamo put out about 22amps. A lot of the alternators used as alternatives are 40amp
I use a small 40amp denso / kuboto type and it seems to cope. I have changed the heater to a modern version after the original leaked.
you can just get a bigger capacity alternator say a 55amp.
or if you are allowed there are some very good LED headlight set ups available which considerably reduces the current required.
The original dynamo put out about 22amps. A lot of the alternators used as alternatives are 40amp
I use a small 40amp denso / kuboto type and it seems to cope. I have changed the heater to a modern version after the original leaked.
you can just get a bigger capacity alternator say a 55amp.
or if you are allowed there are some very good LED headlight set ups available which considerably reduces the current required.
CJD
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Some numbers:
Headlights: 10 amps
Tail lights: 4 amps total
Brake lights: 2 amps
Heater: 5 amps
Ignition: 1 amp
Dash slights: 2 amps
Windscreen wipers: 5 amps
Total with everything that a stock car has to run, running: 29 amps
Dynamo output: 19-21 amps
So, as you can see, if you are in the rain, in the winter, at night, you are on a limited time before your battery runs down! Even adding a radio in fair weather is maxing out the stock generator system. On the other hand, a 40 amp alternator will have no trouble at all powering a stock car plus a little extra.
Headlights: 10 amps
Tail lights: 4 amps total
Brake lights: 2 amps
Heater: 5 amps
Ignition: 1 amp
Dash slights: 2 amps
Windscreen wipers: 5 amps
Total with everything that a stock car has to run, running: 29 amps
Dynamo output: 19-21 amps
So, as you can see, if you are in the rain, in the winter, at night, you are on a limited time before your battery runs down! Even adding a radio in fair weather is maxing out the stock generator system. On the other hand, a 40 amp alternator will have no trouble at all powering a stock car plus a little extra.
