So the ALT light goes out under what conditions?

--

Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
KG6RCR

On 2/21/2007 8:36 AM Mike Collum wrote:

> The 1315 only parallels the batteries when the battery connected to the
> charging system reaches 13.2 volts.
>
> When you first start the engine and the alternator light goes out, the
> aux still isn't connected (and won't be) until the primary battery is
> fully charged.  It'll also drop off the aux battery (even though the
> alternator is still charging) should the primary battery drop to 12.8
> volts ... hence the "Smart" relay designation.
>
> Mike
>
>
>
> Michael Elliott wrote:
>> Thanks for that, Mike.
>>
>> Using the van's ALT light as a trigger to close the bridging relay
>> between the starter and aux relay adds the same "smartness" to the
>> relay system as the 1315 possesses. Even then, if a hosed aux battery
>> drags down the charging system voltage to the point where the ALT
>> light comes on again, the relay would disconnect the aux battery
>> (which would cause the light to go out, bridging the batteries again .
>> . . but the 1315 has a time delay feature which prevents this from
>> happening over and over and over again rapidly. Might just make it
>> happen more slowly.
>>
>> So to me, the 1315 looks like a fine solution, and it's a neater
>> package than my relay + a bunch of wires and things, but it doesn't
>> appear to have any significant advantage over the relay system.
>>
>> This is an interesting thread to me. If anyone can come up with a
>> likely situation where the 1315 trumps my relay rig (below), then I'd
>> like to read about it.
>>
>