User guide

PAGE ４－5
enFORCE Operation Manual
4.3 Calculating Circuit Protection
The chart above shows nominal motor ratings for standard press motors, along with the power
requirements for each SAN unit. Use the formula below to calculate transformer secondary fuse or
circuit breaker sizes.
Transformer (VA)
1.5 x Secondary Voltage 3 = Secondary Fuse Size
Example:
1000 (VA)
1.5 x 200 VAC 3 = 4.33 Amps (Use 5 Amp Fuses)*
* Use a fuse or circuit breaker with the next available highest rating. Due to the high inrush current
at power up, it is recommended to use “Slow Blow” type fuses or fuses rated for motor loads such
as Bussman type FRS or FRN.
RATED VALUES FOR CALCULATING CIRCUIT PROTECTION
MOTOR # OF SAN3 UNITS KVA PER
MOTOR TYPE WATTAGE SAN3 UNIT PER 1 KVA SAN3 UNIT
R1 60 SAN3-24S 8 .125
R2 80 SAN3-24S 6 .167
R3 200 SAN3-40S 2.5 .40
R4 1500 SAN3-120S 0.5 2.0
R5 3000 SAN3-120S 0.25 4.0
Chapter 4: System Setup and Wiring