ENERAC 500 - Page 41

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You must not feed gas to the ENERAC under pressure and you must not starve the
ENERAC's pump for gas. When feeding the gas to the ENERAC you must maintain
a reasonably constant pressure. This is a requirement of all diffusion-type sensors.
Connect the calibration accessory to the ENERAC probe. Make sure the
rubber bulb is inserted past the square grooves located at the probe tip.
Connect the other end of the calibration accessory to the gas cylinder.
Make sure the concentration of the calibration gas is within the range of each
sensor. Do not under any circumstances, use gas that will over-range the sensor
.
The CO span gas can be in the range of 30 - 2000 PPM, 2% accuracy with balance
nitrogen, preferably.
The NO span gas can be in the range of 10 - 2000 PPM, 2% accuracy with balance
nitrogen, required.
The NO
2 span gas can be in the range of 10 - 500 PPM, 2% accuracy with balance
nitrogen, preferably.
The SO
2 span gas can be in the range of 30 - 2000 PPM, 2% accuracy, with balance
nitrogen, preferably.
The combustibles span gas can be in the range of 0.5 - 3 %, with balance nitrogen,
preferably.
(C) Calibration procedure
The following page illustrates the sequence of key strokes to carry out a span
calibration of the analyzer. It is assumed that the instrument has been autozeroed
and there have been no error messages.
1. Autozero the instrument with ambient air.
2. Connect the calibration apparatus and cylinder to the instrument.
3. Press the DATA key and observe the appropriate reading as you open the
calibration cylinder valve. (If you are using the bypass flow meter, adjust the
cylinder valve for a bypass flow rate of approximately 500 cc/min.
4. When the display reading for the desired gas has stabilized press the SHIFT
key to enter the SETUP MENU, and select the SPAN MENU.