Rockwell Automation 1402-LSM Line Synchronization Module Installation Instructions - Manual (Page 16)

Chapter 2
Installation
2–6
Current Transformer Connections
The LSM is equipped with four CT inputs, designated I1 – I4. Inputs I1 – I3
are used to measure the current in the synchronizing circuit. These inputs are
wired as shown on Pages 2–7 through 2–11 in Figure 2.1 through Figure 2.5.
Input I4 is optional and is typically used to measure current in the neutral or
ground conductor. The primary rating for I4 can be different than the primary
rating for transformers I1 – I3. However, the secondary rating for all of the
CT’s must be 5 Amps.
Current connections may remain unused for a system that only performs
synchronization. Unused terminals should be wired to chassis ground for
noise immunity.
The LSM does not require any special maintenance.
The calibration interval for the LSM depends on the user’s accuracy
requirements. To meet general operating requirements, regular calibration is
not necessary.
Contact your nearest Allen–Bradley Sales Office for calibration or service
information.
If the LSM requires servicing, please contact your nearest Allen-Bradley
Sales Office. To minimize your inconvenience, the initial installation should
be performed in a manner which makes removal easy.
1. A CT shorting block should be provided to allow the LSM current inputs
to be disconnected without open circuiting the user supplied CTs. The
shorting block should be wired to prevent any effect on the external
protective relays.
2. All wiring should be routed to allow easy maintenance at connections to
the LSM terminal strips, the swing-arm, and the LSM itself.
!
ATTENTION: A CT circuit must not be opened with primary
current present.. Wiring between the CT’s should include a
terminal block for shorting the CT’s. Open CT secondaries will
produce hazardous voltages, which can lead to personal injury or
death, property damage, economic loss or CT failure.
Maintenance
Calibration
Field Service Considerations