Teledyne API T803 CO2/O2 Analyzer Operation Manual Getting Started
39
3.3.1.7. CONCENTRATION ALARM RELAY (OPTION 61)
The Teledyne API T-Series analyzers have an option for four (4) “dry contact”
relays on the rear panel of the instrument. This relay option is different from and
in addition to the “Contact Closures” that come standard on all TAPI instruments.
The relays have three pins that have connections on the rear panel (refer Figure
3-11). They are a Common (C), a Normally Open (NO), and a Normally Closed
(NC) pin.
Figure 3-11: Concentration Alarm Relay
Alarm 1 “System OK 2”
Alarm 2 “Conc 1”
Alarm 3 “Conc 2”
Alarm 4 “Range Bit”
“ALARM 1” RELAY
Alarm 1 which is “System OK 2” (system OK 1, is the status bit) is in the
energized state when the instrument is “OK” & there are no warnings. If there is
a warning active or if the instrument is put into the “DIAG” mode, Alarm 1 will
change states. This alarm has “reverse logic” meaning that if you put a meter
across the Common & Normally Closed pins on the connector you will find that
it is OPEN when the instrument is OK. This is so that if the instrument should
turn off or lose power, it will change states & you can record this with a data
logger or other recording device.
“ALARM 2” RELAY & “ALARM 3” RELAY
The “Alarm 2 Relay” on the rear panel, is associated with the “Concentration
Alarm 1” set point in the software & the “Alarm 3 Relay” on the rear panel is
associated with the “Concentration Alarm 2” set point in the software.
Alarm 2 Relay CO2 Alarm 1 = xxx %
Alarm 3 Relay CO2 Alarm 2 = xxx %
Alarm 2 Relay O2 Alarm 1 = xxx %
Alarm 3 Relay O2 Alarm 2 = xxx %
The Alarm 2 Relay will be turned on any time the concentration set-point is
exceeded & will return to its normal state when the concentration value goes back
below the concentration set-point.
Even though the relay on the rear panel is a NON-Latching alarm & resets when
the concentration goes back below the alarm set point, the warning on the front
panel of the instrument will remain latched until it is cleared. You can clear the
warning on the front panel by either pushing the CLR button on the front panel or
through the serial port.
07276B DCN6418