Resistor Sizing
The minimum connected resistor to the standard RPM module is 1 ohm. The resistor value can be greater than this but never lower. Use the following procedure to calculate the continuous current rating of the resistor chosen.
1.Tabulate all motion Full Load Amps (FLA)
•½ hour FLA for hoist motion
•1 hour FLA for travel motions
2.Calculate Regen Current for simultaneous motion operation
I |
| ⎛ |
| ⎞ | ⎛ |
| ⎞ |
= ⎜∑FLA | *0.8⎟ | +⎜∑FLA *0.3⎟ | |||||
REGEN | ⎝ | HOIST | ⎠ | ⎝ | TRAVEL | ⎠ | |
3.Size RPM Unit(s) and external resistors as close as possible to calculated value.
Regenerative Power Module - September 2010
Page 11 of 20