Rockwell Automation SB3000 AC Power Modules - Manual (Page 32)

3-4 SB3000 Power Modules (Rittal)
During normal operation, the SB3000 Power Module may also cause a large variation
in the input isolation transformer’s neutral-to-ground voltage in ungrounded and
high-resistance grounded systems. This may cause false ground fault detector
indications.
This type of high frequency, high level line disturbance can be coupled through
standard control transformers into all connected loads, such as electronic power
supplies, I/O cards, and programmable controllers. This coupled, high level noise may
cause improper operation or component failure.
To ensure proper ground fault detector operation, a ground fault detector with a 60 Hz
filter is recommended. Standard magnetic relays and solenoids are not affected by
this high frequency line noise.
3.2.5 Wire Sizes
Input wiring should be sized according to applicable codes to handle the SB3000
Power Module's continuous-rated input current. Output wiring should be sized
according to applicable codes to handle the SB3000 Power Module's continuous-rated
output current. Recommended wire sizes are shown in table 3.4. Terminals should be
tightened to the torque values provided in table 3.5.
!
ATTENTION: The SB3000 Power Module may cause a large variation in
the input isolation transformer’s neutral-to-ground voltage in ungrounded
and high-resistance grounded systems. This type of high frequency, high
level line disturbance may cause improper ground fault detector
operation or component failure.Failure to observe this precaution could
result in damage to, or destruction of the equipment.
Table 3.4 – Recommended AC Input and DC Bus Output Wire Sizes
SB3000 Output Rating Size of Wire
1
1. NEC-recommended cable types: 40 o C (104 o F) copper wire.
445A
2 x 600 Kc Mil (304 mm
2
)
890A
3 x 600 Kc Mil (304 mm
2
)
1335A
4 x 1000 Kc Mil (507 mm
2
)
Table 3.5 – Terminal Tightening Torques
Terminals Tightening Torque
DC Bus Output Power: 45, 47 41 Nm (30 lb-ft)
Ground: GND - Door 11.3 Nm (8.3 lb-ft)
Ground: GND - Hood Access Plate 22.6 Nm (16.5 lb-ft)
Input Power: U, V, W 41 Nm (30 lb-ft)
115 VAC Input Power: L, N 3.5 Nm (2.6 lb-ft)