Teledyne M300EM operation manual Concentration Alarm Relay Option, 19:Concentration Alarm Relay

Optional Hardware and Software Teledyne API – Technical Manual - Model 300E Family CO Analyzers

5.10.CONCENTRATION ALARM RELAY (OPTION 61)

The Teledyne API “E” 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 3 pins that have connections on the rear panel (see Figure 5-19). They are a Common (C), a Normally Open (NO), & a Normally Closed (NC) pin.

Figure 5-19: 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 loose 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	CO Alarm 1 = xxx PPM
Alarm 3 Relay	CO2	Alarm 2 = xxx PPM
Alarm 2 Relay	CO Alarm 1 = xxx PPM
Alarm 3 Relay	CO2	Alarm 2 = xxx PPM

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.

In instruments that sample more than one gas type, there could be more than one gas type triggering the Concentration 1 Alarm (“Alarm 2” Relay). For example, the M300EM instrument can monitor both CO & CO2

80 04288D DCN5752