Lenze MCH Series - Manual (Page 26)

22 13435744_EDBMH01_v13
8 INPUT AC REQUIREMENTS
WARNING!
Hazard of electrical shock! Disconnect incoming power and wait
three minutes before servicing the drive. Capacitors retain charge
after power is removed.
8.1 INPUT AC POWER REQUIREMENTS
8.1.1 VOLTAGE
The input voltage must match the drive’s nameplate voltage rating. Voltage fluctuation
must not vary by greater than 10% overvoltage or 15% undervoltage.
NOTE
Drives with dual rated input voltage must be programmed for the
proper supply voltage. Refer to Parameter 0 - LINE VOLTS in
Section 18.0 - DESCRIPTION OF PARAMETERS.
The UL file for this drive shows that it is suitable for use on a circuit capable of delivering
not more than 200,000 RMS symmetrical amperes, at the drive’s rated voltage. The
CSA file identifies a short-circuit withstand rating of 5,000 RMS symmetrical amperes
at the drives rated voltage.
Three phase voltage imbalance must be less than 2.0% phase to phase. Excessive
phase to phase imbalance can cause severe damage to the drive’s power components.
Motor voltage should match line voltage in normal applications. The drive’s maximum
output voltage will equal the input voltage. Use extreme caution when using a motor
with a voltage rating that is different from the input line voltage.
8.1.2 SUPPLY TRANSFORMER kVA RATINGS
If the kVA rating of the AC supply transformer is greater than ten times the input kVA
rating of the drive, a drive isolation transformer, or a 2 - 3% input line reactor (also
known as a choke) must be added.
8.2 INPUT FUSING AND DISCONNECT REQUIREMENTS
A circuit breaker or a disconnect switch with fuses must be provided in accordance with
the National Electric Code (NEC) and all local codes.
The MCH drive is capable of withstanding up to 120% current overload for 60 seconds.
Select a fuse or magnetic trip circuit breaker rated at 1.25 times the input current rating
of the drive (the minimum size should be 10 amps, regardless of input current rating).
Refer to Section 5.0 – MCH RATINGS.
Minimum voltage rating of the protection device should be 250 Vac for 240/200 Vac
rated drives, and 600 Vac for 480/400 Vac and 590/480 Vac drives. Current limiting type
fuses should be used when input fusing is required. Select fuses with low I 2 T values,
rated at 200,000 AIC. Recommended fuses are Bussman type KTK-R, JJN and JJS.
Similar fuses with equivalent ratings by other manufacturers may also be acceptable.
WARNING!
Per UL requirements, use a FUSE (not a circuit breaker) for 240VAC drives
requiring >40A protection and for 480VAC & 600VAC drives requiring
>32A protection.