Tom/Barb
Oak Harbor
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Try this, solder a wire to the side of a 12 volt bulb such as a tail light bulb, and another wire to the hot connection of the bulb.
then at every connection of the heavy wire portion of the electrical system, attach the wires to the side of each connection with the system on. if the light lights you have a bad connection.
that's the easy way to do a voltage drop test. if the connection has any resistance across the connection, the light will light.
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1L243
Astoria, Oregon
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This is my friends Bounder. The Coach had been plugged in for three days. I was using a Voltminder plugged into the DC outlet wired through a 20amp circuit. Two lights also run on this circuit. I got a reading from the DC outet right after unplugging from shore power and tested the batteries directly with a volt meter. There was about 1/10 volt drop from the batteries to the DC outlet. Like 13.5 at the batts and 13.4 at the DC outlet. I turned on all the cabin lights and the volts dropped below 12 volts even before I got the last light turned on. (unfortunately I did not test at the batteries at this point). The wires on the DC outlet are 10 gage wire connected to 12 gauge wire. I would not have thought that the voltage drop would have been so sudden. After turning all the lights back off, Voltminder showed 12.75 and climbed to 12.95 volts. ( I realize that this level would be less if the batteries had a chance to rest after charging).
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smkettner
Southern California
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I think much of the drop is in the wiring. Best to check directly on the battery terminals.
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FuzzyKnight
Santee, Ca
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It is normal as each time you turn on a light or some kind of drain on a DC system it will lower the voltage reading. If you turn everything off it will go back up.
DC 101 - If you have clearance lights on the top of the coach and measure the voltage at each light, lets say you have 5 lights, The first light will show 10 volts. The second will show 8 volts. The third will show 6 volts. The forth will show 4 volts and the last will show 2 volts and it will show Zero on the ground side because each light will consume X amount of voltage.
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1L243
Astoria, Oregon
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Assuming that is true would it make a difference if all these lights are on 3 different ciruits? Tomorrow I will go over and try again. This time I will measure at the battery when all the lights or are and compare that with the DC outlet..
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OnaQuest
Old enough to be a
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FuzzyKnight wrote:
DC 101 - If you have clearance lights on the top of the coach and measure the voltage at each light, lets say you have 5 lights, The first light will show 10 volts. The second will show 8 volts. The third will show 6 volts. The forth will show 4 volts and the last will show 2 volts and it will show Zero on the ground side because each light will consume X amount of voltage.
Not true. The clearance lights are wired in parallel and would have the same 12 volts across any of the five lights. What you described is a series arrangement which is never used in automotive/RV DC wiring.
DC 101-A.
The only lights I've ever seen wired in series are "Christmas Tree lights".
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slemnah
none
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And that would be the old style Christmas lights.... the new lights are connected in parallel
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OnaQuest
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slemnah wrote:And that would be the old style Christmas lights.... the new lights are connected in parallel
Exactly.....
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Ivylog
Blairsville, Ga. USA
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I see some LED lights in your future as they will solve your problem. These are the best I've found for less than $4 for those dual bulb lights that use a 1156.
This post is my opinion (free advice). It is not intended to influence anyone's judgment nor do I advocate anyone do what I propose.
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jauguston
Bellingham, WA
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What is not functioning properly that you are trying to fix?
Jim
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