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P80 - Getting home on battery power - House DC current measurements

Help, Advice and DIY Tutorials on Volvo's P80 platform cars -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, including 850 R, 850 T-5R, 850 T-5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70

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abscate
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P80 - Getting home on battery power - House DC current measurements

Post by abscate »

I must have threatened to make this measurement for a decade now - I finally converged on hood up and ammeter in hand during my new career as a model

This thread answers the question - if my alternator dies, how long can I run on a full charged battery??

Idle house load is about 5-6 Amps through the kidney fuse box, confirmed by looking at the alternator resupply through the Positive battery cable

With lights and fan on it goes to 15 amps.

So to 50% battery, you will get 5 -6 hours driving time daytime, at night 2-3 hours dirving time, if you start with a battery at 100% SOC in good condition.

I would half those times for a battery over 3 years old.
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Empty Nester
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850 LPT
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Post by 850 LPT »

:lol: You have too much time on your hands
98' S70, base, 5-speed manual, pewter/ tan, 145k miles
99' S70, base, 5-speed manual, nautic blue/ tan, 225k miles, currently inop
06' V70, auto, willow green/ charcoal, 147k miles
79' Ford Capri S, Euro Spec 2.8 V6, T9 5-speed manual, owned since 1986
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Post by scot850 »

Does this work for all P80's? What about the 99- which don't like low voltages?

Neil.
2006 V70 2.5T AWD Polestar tune
2000 V70 R - still being an endless PITA
2006 XC70 - Our son now has this and still parked in our garage
2003 Toyota 4Runner V8 Limited
2015 Kia Sportage EX-L - Sold
1993 850 GLT -Sold
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1997 Volvo 850 SE NA - Went to niece in California - Sold
2000 V70 SE NA - Sold

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abscate
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Post by abscate »

You can probably squeak some extra time on a -1998 as it is less electronic. Poorer ignition efficiency and some more draws like IAC valve and such.

Battery at 50% on any electronic car (and transmissions are electronic too) is a good limit point - you are on borrowed time after that.
Empty Nester
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Post by volvolugnut »

Your battery mileage may vary.
volvolugnutr
The Fleet:
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abscate
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Post by abscate »

I seem to recall one of you guys had a kid in Colorado who had to drive on a battery. Did that experiment mesh with theory above?

Dirk or erikv maybe?
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