BOOK0795-F
4
4. BRANCH CIRCUIT PROTECTION - The National Electrical Code requires that a two-pole fused dis-
connect switch be installed in the AC line supply to the controller. Although an optional two-pole circuit
breaker (Option 1010) is available for Model 2601 Controllers, this circuit breaker should not be consid-
ered as branch circuit protection. However, the existing branch circuit may already provide the required
protection. Refer to the National Electrical Code and local codes.
5. LINE SUPPLY - The controller should not be connected to a line supply capable of supplying more than
100,000 amperes short-circuit current. Short-circuit current can be limited by using an input supply trans-
former of 50 KVA or less, or by using correctly sized current limiting fuses in the supply line ahead of the
controller. Do not use a transformer with less than the minimum transformer KVA listed in Table 9, page
33.
If rated line voltage is not available, a line transformer will be required. If the line supply comes directly
from a transformer, place a circuit breaker or disconnect between the transformer secondary and the con-
troller. If power is switched in the transformer primary, transients may be generated which can damage the
controller. See Table 9 (page 33) for minimum transformer KVA.
Do not use power factor correction capacitors on the supply line to the controller.
A 12-joule metal oxide varistor (MOV) is connected across the controller terminals. If higher energy tran-
sients are present on the line supply, additional transient suppression will be required to limit transients to
150% of peak line voltage.
When a 115 VAC line supply is used, connect the white (common) wire to Terminal L2 and connect the
remaining (hot) wire to Terminal L1.
6. ISOLATION TRANSFORMER - While not required, an isolation transformer can provide the following
advantages:
a. Reduce the risk of personal injury if high voltage drive circuits are accidently touched.
b. Provide a barrier to externally generated AC supply transients. This can prevent controller damage from
abnormal line occurrences.
c. Reduce the potential for damaging current if the motor armature, motor field, or motor wiring become
grounded.
7. GROUNDING - Connect the green or bare (ground) wire of the line supply to the ground screw located
near the top conduit entry hole in the controller base. Then ground the controller base by connecting the
ground screw to earth ground.
The motor frame and operator control stations must also be grounded.
Personal injury may occur if the controller, motor, and operator stations are not properly grounded.
8. WIRING PRACTICES - The power wiring must be sized to comply with theNational Electrical Code,
CSA, or local codes. Refer to the controller data label for line and motor current ratings.
Do not use solid wire
To Next Page
Loading...
Need help?
General
