7835
Hydrazine Monitor
4 Electrical Installation
10
IM/7835–EN Rev. P
4.4 Transmitter Unit – Ancillary Equipment
4.4.1 Recorders
The choice of 2 different isolated recorder output signals
enables the monitor to be used with a wide variety of recording
and data processing equipment. A 2-pen recorder is necessary;
pen 1 indicating the hydrazine concentration and pen 2 the
monitor range.
4.4.2 Range Indication
The remote range indication relays can be used in different
arrangements to suit the requirements of the installation. The
relays can, for example, be wired directly into the PLC or data
logger but, if a recorder is used, a method of indicating the
range set is required.
Suitable range indication recorder input can be provided using a
resistor network that consist of 4,
1
/
4
watt resistors. Connect the
network as shown in the two examples in Fig. 4.4. A recorder
with suitable voltage and resistance inputs can be provided by
ABB. The recorder provides 60 % scale deflection for Range 1
and 70 % scale deflection for Range 2.
Ensure other arrangements are designed to suit the
requirements of the system. Ensure that all external equipment
is set up and working according to the instructions supplied.
4.5 Sensor Unit – Access to Terminals
Referring to Fig. 4.5:
1. Unlock the door
A
and open fully.
2. Remove all 4 screws
B
and remove the terminal cover
plate
C
.
Fig. 4.4 Resistor Network for Remote Range Indication
(0 to 100
Ω
and 0 to 100 mV Input Options)
0 to 100
Ω
Input
0 to 100 mV Input
39R
30R
To Chart
Recorder
30R
Range 1
Range 2
39R
30R
To Chart
Recorder
30R
Range 1
Range 2
10 V DC External Supply
0 V
10K
Warning.
Isolate the transmitter from power supplies
before removing the cover.
Fig. 4.5 Sensor Unit – Access to Terminals
A
B
C
