Dometic SI 1500-12V Manuel De L'utilisateur page 13

3-4-5. Set the power switch to the ON position. Check the meters and
indicators on the front panel of the inverter. The voltage bar
graph should indicate 11 to 14 volts (22 - 28V when 24V
version is used) depending on the voltage level of the power
source. If there is no indication, check your power source and
the connections to inverter.
The other indicators should be off.
3-4-6. Set inverter switch to the OFF position, the indicator lights may
blink and the internal alarm may sound momentarily.
This is normal. Plug the test load (maximum 1500W resistive
load) into the AC receptacle on the front panel of the inverter.
Leave the test load switched off.
3-4-7. Set inverter switch to the ON position and turn the test load On.
The inverter should supply power to the load. If you plan to
accurately measure the true output r.m.s. voltage of inverter, a
meter such as FLUKE 45, BECKMAN 4410 or TRIPLETT 4200
must be used. (True RMS multimeter must be used).
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