OZONE MONITOR BMT 932 Manual, Rev. 02/2021
16
Signal Name
Pin No.
Description
Alarm High Open
6
Pins 4-6 opened when HIGH alarm
4-20 mA (GND)
7
Current loop output return
4-20 mA
8
Current loop output
Voltage Outputs (GND)
9
Voltage outputs return
Voltage Output 1 V
10
Max. concentration Range = 1 V
Voltage Output 10 V
11
Max. concentration Range = 10 V
Lamp Low
12
Relay contact
Lamp Low
13
Pins 12-13 open when LAMP LOW
Error Common
14
Relay contact
Error Closed
15
Pins 14-15 closed when error
Error Open
16
Pins 14-16 opened when error
Relay Outputs: the Alarm Relay contacts will operate at a max. voltage of 28 V (DC or AC) and a
max. current of 1 A. Further details of the Alarm Relays operation are described in section 15 on
page 31. The Error Relay and Lamp Low Relay will switch 28 V (AC or DC) at a max. current of
1 A. All relays are in the alarm/error position if no power is applied to the instrument.
Analog Outputs: The analog outputs are updated with every new measurement (about every 20
seconds).
The voltage outputs are isolated voltage signals 0 to 10 V and 0 to 1 V, proportional to the con-
centration (actually the 0 - 10V signal swings down to about -0.25 V below zero). Input resistance
of the load should be higher than 1 k
.
The current output is an isolated current signal 4 to 20 mA, proportional to concentration (with
an offset of 4 mA). Input resistance of the load should be less than 600
(optional 1350
).
The current output provides the energy for the curent loop.
Attention:
The current output must not be connected to an external power supply
!
11.3
Channel Identification
The green terminal block named "CHANNEL ID” provides six semiconductor relay contacts
with information on which sample channel the analog output concentration signal corresponds
to. A closing relay identitfies a channel.
Signal Name
Pin No.
Description
Channel 1
1
Output from sample on Channel 1
Channel 2
2
Output from sample on Channel 2
Channel 3
3
Output from sample on Channel 3
Channel 4
4
Output from sample on Channel 4
Channel 5
5
Output from sample on Channel 5
Channel 6
6
Output from sample on Channel 6
Common
7
Common contact for all relays
