Emerson Unidrive M700 User Manual page 48

Drives of low power rating may also be susceptible to disturbance when connected to supplies with a
high rated capacity. Line reactors are particularly recommended for use with the following drive
models when one of the above factors exists, or when the supply capacity exceeds 175 kVA
03200050, 03200066, 03200080, 03200106,
03400025, 03400031, 03400045, 03400062
Note the current rating of the AC input line reactors should be as follows:
Current rating
Peak current rating
5.3 DC supplies
The following section provides guidance for the selection of a suitable DC supply for use with the
drive. The working voltage range of the low voltage DC supply is as follows:
DC operating supply voltage range and levels
Pr 06.066 - Low
Drive Min
Under Voltage
model Vdc
200 Vac 24
400 Vac 24
575 Vac 24
690 Vac 24
For UL compliance only, the maximum supply symmetrical fault current must be limited to 100 kA
Minimum and maximum voltage values include ripple and noise. Ripple and noise values must not
exceed 5 %.
5.2.1 Low voltage DC supply types
The Low voltage DC supply may be connected to ground or left floating. In the event of a contactor
sticking, high voltage would be present at the negative terminal of the drive. The instructions following
ensure user safety in both cases.
5.2.2 Systems with an isolated DC supply
The supply can be floating with respect to ground, although it may have a high impedance ground to
drain leakage currents. In the event of a fault where AC and DC supplies are connected at the same
time a high current would have no fault path to ground.
In this case:
•
The user 24 Vdc, +DC, -DC Bus terminals of the drive and DC terminals of the Low voltage DC
supply must be protected from user contact.
•
The Low voltage DC supply must be able to withstand mains potential with respect to ground and
be suitable for use in an industrial environment (category 2 supplies).
•
Cables rated for the voltage of the rectified AC supply must be used to connect the drive to the
Low voltage DC supply.
In the event of a fault the user 24 Vdc, +DC, -DC Bus terminals of the drive and DC terminals of the
Low Voltage DC source (including any wiring between) could be at a potentially lethal voltage.
5.2.3 Systems with a grounded DC supply
2
If the I t of the ground connection is not greater than that of the fuses used, then the external user 24
Vdc supply terminal and associated wiring could be at a potentially lethal voltage in the event of a
fault.
The ground connection for the supply must be a high constant current connection with an I
greater than the fuses. This is so that in the event of a fault where AC and DC supplies are connected
P a g e | 48
= Not less than the drives continuous Heavy Duty input current rating
= Not less than twice the drives continuous Heavy Duty input current rating
Pr 06.065 -
Standard
Under Voltage
Threshold
Threshold
175
330
435
435
Standard
supply
loss level
175 205
330 410
435 540
435 540
Max Over voltage
Vdc trip
339 415
679 830
813 990
976 1190
2
t rating