Littelfuse Startco FPU-32, Manual

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Page 3-3
FPU-32 Feeder Protection Unit
Rev. 2-A-103014
System Wiring
3.2.1.7 RS/EIA/TIA-232 C
OMMUNICATIONS
An RJ-45 TIA-232 connector is provided on the rear
panel of the FPU-32. This port uses the Modbus

RTU
protocol to communicate with SE-Comm-RIS PC-interface
software. For Modbus

RTU protocol, see Appendix C.
The slave ID and communication baud rate are set in the
Setup

Hardware

Local Comms menu.
Table 3.1 shows the pinout for the optional CA-945
adapter for operation with SE-Comm-RIS. See Fig. 3.1 for
RJ-45 pinout. For a USB connection, use a SE-ICUSB232
adapter.
TABLE 3.1 CA-945 A
DAPTER
N
AME
RJ-45 DB9
RI/DSR 1 9
CD 2 1
DTR 3 4
SG 4
(1)
5
RD 5
(1)
2
TD 6
(1)
3
CTS 7 8
RTS 8 7
(1)
Minimum requirement for communications.
3.2.2 MPU-CIM C
ONNECTIONS
The MPU-CIM CT-input terminal blocks accept 22 to
10 AWG (0.3 to 4.0 mm
2
) conductors. The remaining
MPU-CIM clamping blocks accept 24 to 12 AWG
(0.2 to 2.5mm
2
) conductors.
The MPU-CIM contains four signal-conditioning
interface transformers which are interconnected as shown
in Fig. 3.5. These transformers isolate the FPU-32 from
the phase and earth-fault CT's. The MPU-CIM eliminates
the need for CT shorting contacts when the FPU-32 is
disconnected. Phase-CT and earth-fault-CT secondaries
can be simultaneously grounded through terminal 22 and a
jumper to terminal 20. For applications where the CT
secondaries must be grounded at another location, the CT
secondaries can be isolated by removing shorting screws
A, B, and C through holes in the bottom of the MPU-CIM.
See Figs. 2.3 and 3.5.
N
OTE:
A-B-C phase sequence and polarity must be
observed when connecting phase CT’s. See Section 4.2.1.
Connect the MPU-CIM to the FPU-32 as shown in
Figs. 3.6 and 3.7 using the cable provided with the
MPU-CIM.
TB3 TB2
27 26 25 24 23 22 21 20 19 18 17 16 15 14 13
1
R 5 S E X Y
E
F
1 E
F
2 C
O
M
C B A
A
B
C
R S 5 1 R S 5 1 R S 5 1
1 2 3 4 5 6 7 8 9 10 11 12
TB1
NOTES:
1. REMOVE SHORTING SCREWS A, B, AND C TO ISOLATE PHASE-CT
AND EARTH-FAULT-CT SECONDARIES FOR IN-LINE APPLICATIONS.
2. SHORTING SCREWS A, B, AND C: 6-32 x 0.375
NICKEL-PLATED-BRASS BINDING HEAD. DO NOT SUBSTITUTE.
3. SHORTING SCREWS A, B, AND C MUST NOT BE REMOVED FOR
RESIDUAL OR TWO-CT CONNECTIONS.
4. EACH TERMINAL ON TB1 AND TB3 WILL ACCEPT ONE
NO. 10 AWG CONDUCTOR.
FIGURE 3.5 MPU-CIM Schematic.