User's Manual

044-05156 Rev C 45
subrack. The SIM is internally terminated, as are each of the amplifier subracks, to prevent loading down the RS-
485 buss.
Pin # Description
1 RS-485 TX data +
2 RS-485 TX data -
3 RS-485 RX data +
4 RS-485 RX data -
5 No Connection
6 No Connection
7 No Connection
8 No Connection
9 No Connection
Descriptions TX and
RX are in reference to
the MCPA subrack.
TX refers to data in to
the SIM.
RX refers to data out
from the SIM.
Amplifier alarms are reported to the SIM via the amplifier subrack RS-485 bus. The amplifier subracks are daisy-
chained on the RS-485 bus, and the alarm bus is cabled from the subrack rear panel to the front panel subrack
interface panel. Each subrack has a unique address. The subrack address is set via front panel dip switches.
Refer to Amplifier Monitoring in the MCR21929-1-2 Amplifier Subrack section of this manual for available alarms.
4.9.2 DLNA Alarms - DLNA Interfaces (J7 – J12)
The DLNA interface is accomplished with six DB15 Female connectors. Each connection is unique and requires
coordination with the DLNAs within the cabinet. Each connector provides DC power to the DLNA, differential I
2
C
BTS pass-through, and analog temperature signals.
DC power provides the DLNA with +27±1.0 Vdc via a 5A maximum circuit breaker on four contacts (2-source, 2-
return). The circuit breaker also functions as the power switch to the DLNA.
The differential I
2
C interface utilizes 6 contacts. These signals are passed-through the SIM to the BTS interface. A
module detect signal is also passed through. No processing is provided or required.
A single analog voltage signal (pin 10) represents the temperature of the DLNA module. The voltage potential is
with respect to the DC return. The temperature conversion factor is: 0°C = 500mV +10mV/°C.
PIN Description PIN Description
1 DC Source 9 Module Detect
2 DC Source 10 Temperature Signal
3 DC Return 11 No Connection
4 DC Return 12 No Connection
5 No Connection 13 SCL-
6 SCL+ 14 SDA_TX-
7 SDA_TX+ 15 SDA_RX-
8 SDA_RX+
4.9.3 Power Plant Alarms - Rectifier Interface (J13)
The Rectifier interface is accomplished through a single DB9 Male connector. This interface includes up to six
individual rectifier faults. The faults signals are open collector. The signal impedances are defined as:
Low impedance signifies normal operation
High impedance signifies a fault