Yaskawa GPD 506/P5 Section One - Manual (Page 21)

PP.P5G5.01.Troubleshoot
Page 21
Rev. 06/11/2003
The soft charge resistor/contactor will change with the capacity of the inverter. 7.5kW and
smaller models use resistors mounted on the power board. 11kW and 15kW models use a
single resistor mounted in the main circuit. In 230V units 1.5kW and smaller and 460V units
4.0kW and below, the contactor is soldered to the powerboard.
Soft Charge Resistor Check for 0.4 kW through 15 kW models:
The first step is a visual inspection. Many times a damaged soft charge resistor has physical
damage, such as burn marks, discoloration, or has been broken into pieces. If there is no
physical evidence of damage, a check with an ohmmeter must be performed. Locate the soft
charge resistor(s) inside the inverter unit. With an ohmmeter set to the R x 1 scale, measure
across the resistor(s). If the resistor(s) is damaged, the measured value will be infinite ohms
(burned open).
Soft Charge Contactor Check for 0.4 kW through 15 kW models :
With an ohmmeter set to the R x 1 scale or the ohm setting, measure across the contacts
and press in the plunger. On the smaller capacity inverters, the contactor will be totally
enclosed and this step can not be performed. When the plunger is pushed in, the resistance
across the contacts should read 0 ohms. When the plunger is released, the resistance will be
the ohmic value of the soft charge resistor. On the units with the board mounted contactor,
verify that the contacts read infinite ohms across each contact. Measure across the coil of
the contactor, it should read about 300 ohms.
Soft Charge Resistor/Contactor