ITT S-DRIVE IM213 User Manual

Hazardous

voltage

Hazardous

voltage

The line input voltage and transformer power must meet certain phase and balance requirements. If you or 

for installation. When in doubt contact the local power utility or the factory.

Before connecting power to the controller measure the line to line and line to ground voltage from the power

source. The line to line voltage must be in the range of 195Vac to 265Vac (230V +/– 15%) for 230V models

and 391Vac to 529Vac (460V +/– 15%) for 460V models. The maximum phase to phase imbalance is +/– 3%.

If the phase to phase imbalance is greater than +/– 3% then an isolation transformer may be necessary. The

line to ground voltage must be less than 110% of the nominal (230V or 460V) line to line voltage. If the line to

ground voltage is not in this range the EMC filter and MOV components may need to be removed (see section on

“Ungrounded secondary” transformers) or an isolation transformer with a grounded secondary may be necessary.

If an isolation transformer is used, the best choice is ONE three phase, six winding transformer. A delta primary

is best for third harmonic cancellation. A wye secondary avoids circulating current problems and provides the

very desirable option of grounding the secondary neutral for minimum voltage stress and ripple to ground. The

transformer should have a KVA rating at least 1.1 times the maximum connected HP. A K factor of 6 is sufficient

if transformer impedence is greater than 2%. A K Factor of 5 is sufficient if transformer impedence is greater

than 3%. The transformer manufacturer may provide derating for non K Factor rated transformers to operate at

the drive produced K Factor levels.

Other transformer configurations are acceptable. Three single phase transformers can be used if they are 

identical for phase to phase symmetry and balance. A wye connected primary neutral should never be

grounded. Great care should be taken with delta primary delta secondary configurations. Any lack of phase to

phase symmetry could result in circulating currents and unacceptable transformer heating.

Never use phase converters with drives as nuisance tripping and possible damage may

occur. Instead, use single phase input power and 50% derate factor.

“Open Delta” power systems should be sized using the 50% derate factor.

Consult factory.

Run the motor lead wire from the motor or conduit box through metal conduit to the bottom of the

controller. Use metal conduit and metal conduit connectors. Size the conduits according to the NEC,

CEC or local codes. Connect conduit and insert the wires through the second or third opening from the

left. Choose the opening that fits or is larger than the conduit used. If the opening is larger than the conduit,

use conduit bushings to attach the conduit to the controller.

Hazardous

voltage