GDC-350 Operation Manual
5909-9000 Rev 1
23
Therefore, in this example, the required voltage setting to achieve an alarm set point
of 100 ppm is 2.0 VDC.
VOLTAGE REFERENCE TABLE FOR ALARM SETTINGS
SENSOR /
GAS
MEASUREMENT
RANGE
LOW ALARM
SET VOLTAGE
HIGH ALARM
SET VOLTAGE
CO
0-200 ppm
25 ppm / 0.50 VDC
100 ppm / 2.00 VDC
NO
2
0-10 ppm
0.7 ppm / 0.56 VDC
1.5 ppm / 1.20 VDC
O
2
0-25.0% Vol
19.5% Vol./ 3.12 VDC 23.0% Vol. / 3.68 VDC
NO
0-100 ppm
25 ppm / 1.00 VDC
50 ppm / 2.00 VDC
SO
2
0-20 ppm
2 ppm / 0.40 VDC
5 ppm / 1.00 VDC
Combustibles
0-50% LEL
20% LEL / 1.60 VDC
40% LEL / 3.20 VDC
Refrigerant
Gases
(R series)
0-2000 ppm
500 ppm / 1.00 VDC
1000 ppm / 2.00 VDC
4.6. Relay Time Delays
The GDC-350 offers a wide range of time delay settings that are user configurable. If
the GDC-350 has been equipped with the LED digital display, read the values on the
display as you change them to suit your application. If the GDC-350 does not have a
digital display, you will need a volt meter. The voltage reference is 0-4 VDC.
Attach the volt meter leads to the two test points (TP1 and TP2) located just below the
high alarm relay (RLY2) on the main circuit board.
