3.4. Fuses
It is required that user supplied fuses be installed as described below.
External fuses should be installed in the meter voltage tap to the main lines, near the
meter housing. 600 V 1/2 A BUSS type KTK-R-1/2 Fast Acting or equivalent fuses are
recommended for the Power Xpert
®
Meter VT connections.
External fuses should be installed in the potential transformer lines as specified in the
National Electric Code (NEC) for the specific application.
The power supply wiring should be fused or put on a breaker sized to protect the wire.
3.5. Hipot and Megohm (Megger) Testing
CAUTION
DO NOT HIPOT OR MEGOHM TEST THE METER. SEVERE DAMAGE TO THE METER
CAN RESULT.
3.6. Communication Wiring
The Power Xpert
®
Meter (PXM 4000/6000/8000) has inverted terminal blocks for CM4 -
the 24V Auxiliary I/O Power and CM6. These inverted terminal blocks prevent the user
from crossing 24v source and communication terminals.
RS485 fail safe biasing resistors are used at each master port.
Eaton strongly recommends using ferrules when connecting to a terminal block.
When connecting to a terminal block, the twisted pair sensitivity is critical for COM0,
COM1, and COM2. This means that the Data A wire must match up with terminal DA
(-) and the Data B wire must match up with terminal DB (+). See section 3.9 for further
explanation.
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IB02601007E
Page 21
3. Mounting and Wiring
Figure 11:
3-Phase 4-Wire Y (Above 600 Volts). External Voltage Transformers and Current Transformers.