Settings and Calibration | Model 7500ZA | |
|
|
|
Setting Range |
|
Alarm value: | → 5 ppm step (initial value: 500 ppm) |
Alarm count: 1- 99 times/hr | → (initial value: 5 times) |
Hysteresis : | → (initial value: 0% of full scale) |
[% FS] represents the percentage with the CO range regarded as 100%.
Action of Peak Alarm
If the CO concentration exceeds the alarm value, counting will begin. If the number of peaks is over the set times per hour, a peak alarm contact output becomes closed (ON). If it is less than the set times per hour, it is open (OFF). Since 5 peaks /hour is exceeded in the cross- hatched area marked (1) in the above graph, the peak count alarm is turned ON. Since peaks of more than 5 per hour occur at the interval between (1) and (2), the peak count alarm remains ON whereas at (2), peaks are reduced to 4 per hour, and the alarm is turned OFF.
Like the hysteresis of the alarm setting, the hysteresis prevents possible chattering when a measured gas fluctuates about the alarm value.
*The peak alarm counting logic is not performed during the first 10 minutes after the power is turned ON.
Teledyne Analytical Instruments | 48 |
