Voltage in Travel Trailer
When I am plugged into 30 amp , the meter inside coach shows 120 volts. When furnace runs meter drops to approx 117 volts. Wife. Carries a hotpot to boil water. Turning on the pot when furnace ru...
Forum Discussion
scrubjaysnest wrote:
This isn't likely to be normal.
Of course voltage drop is "normal" and the degree to which an unloaded nominal voltage source of 120 vac will drop once a load is placed on the circuit will vary depending on a number of a factors which include total load, cable length, cable gauge, and therefore cable resistance. One can easily estimate just what the voltage drop will be by plugging a series of numbers into a Voltage Drop Calculator. Trailers designed for 30 amp main service are wired with 10 gauge cable ... this screenshot illustrates voltage drop for a 30 amp load over 25' of 10 gauge main service cable so one could even extrapolate from this just what the drop would be for other values without even using the calculator. For example, if the load was just 15 amps over the same length of 10 gauge cable the voltage drop would also be half - i.e. 0.75 volts instead of 1.50 volts.
