Kollmorgen MMC Smart Drive Series, Hardware Manual

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60 Kollmorgen - June 2014
MMC Smart Drive Hardware Manual
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SYSTEM POWER DEVICES
of 1.5 is used with a three phase system. This factor should minimize the effects of the
secondary line voltage sagging in the transformer during peak current periods.
The speed/torque curve information for 230V motors is based upon a drive input
voltage of 230V AC. For a 115V AC input voltage, the maximum speed can be
reduced up to one half.
Example single phase Formula:
Example three phase Formula:
4.5 External Shunts
Power from the motor is returned to the MMC Smart Drive during motor deceleration.
Excessive power may have to be dissipated from the MMC Smart drive when large
inertia loads are present. External shunts should be used to avoid excessive bus over
voltage faults.
This section covers three aspects of External Shunts:
• Refer to section 4.5.1 on page 60 for information on choosing External Shunts.
• Refer to section 4.5.2 on page 62 for information on mounting External Shunts
• Refer to section 4.5.3 on page 69 for information on connecting External Shunts
4.5.1 Choosing External Shunts
This section describes how to select the proper External Shunt based on system
parameters.
Kollmorgen recommends you use the Motion Solutions Sizing Software to determine
the need for and type of external shunt. However, you may perform the following
calculations to choose the external shunt for your application.
1. Obtain the Peak Generating Power for the drive in watts (W).
2. Perform the following calculation:
W x T = Watts/sec or Joules
NOTE
For 460V drives, the 3-Phase source powering the drive has to be a center-
grounded “Y” configuration. Do not exceed 304 Volts RMS from any phase
to ground.
For 220V drives, the 3-Phase source powering the drive does not have to be
a center-grounded “Y” configuration. Do not exceed 152 Volts RMS from any
phase to ground.
KVA
Speed RPM
 
Torque lb in –
  
63 025

------------------------------------------------------------------------------
0.746 KVA

HP
------------------------------ 2.0
 
=
KVA
Speed RPM
 
Torque lb in –
  
63 025

------------------------------------------------------------------------------
0.746 KVA

HP
------------------------------ 1.5
 
=