Operating Instructions

SED2 VFD Startup, Operation, and Maintenance Manual
84 Siemens Building Technologies, Inc.
3. Close unit.
4. Remove lockout, tag-out materials.
Re-energize Unit
1. Verify 3-phase power supply is within SED2 ratings.
2. Check for input phase balance legs: A to B, B to C, and C to A.
Phase balance should be within 10V to 15V of each other.
DC Bus Integrity Test
1. At this time, the SED2 should have power applied but not be enabled
to run.
2. Check the Actual DC Link Voltage using parameter r0026 index 000
and 001.
• With index 000 displayed, there should be no more than a 25V
fluctuation.
• With index 001 displayed, there should be no more than a 25V
fluctuation.
Contactors and Switches
Verify with infrared temperature that no hot spots have occurred in
contactors and switches.
Motor Bearing Wear
To determine motor bearing wear, use an amphere probe at 60 Hz on
SED2 motor output leads to document full running amps.