Campbell Scientific AP200 CO2/H2O Atmospheric Profile System - Manual (Page 30)

AP200 CO
2
/H
2
O Atmospheric Profile System
Pump Temperature: The temperature of the pump module is reported in
public variable pump_tmpr. The operating range of the pump is 0°C to 55°C.
If the pump temperature is outside this range, the AP200 will disable the pump.
The pump module has a heater (8 W) that turns on if the pump temperature
falls below 2°C. If the AP200 is started at cold temperature, it may take up to
50 minutes to warm the pump module (from –30°C to 0°C). When it reaches
2°C the heater will cycle on/off as needed to maintain this temperature. The
fraction of time the pump heater is on is reported in the output tables ( IntAvg,
CalAvg, and SiteAvg) as pump_heat_Avg. Once the pump is warmed up and
starts running, it will normally keep itself warm without additional heat to
approximately –30°C ambient.
The pump module has a fan (0.7 W) that turns on if the pump temperature rises
above 50°C. The fan will stay on until the pump temperature falls below 45°C.
The fraction of time the pump fan is on is reported in the output tables
( IntAvg, CalAvg, and SiteAvg) as pump_fan_Avg. This will typically
increase from zero at 20°C ambient temperature to 0.5 (0.4 W average power)
at 45°C.
The outlet of the pump connects to a small volume to reduce noise, and then to
the Exhaust fitting on the bottom of the system enclosure. This fitting has a
screen to prevent insects or debris from entering when the pump is off. If
exhausting the air samples at this location is a problem (for example, if it is
close enough to an inlet to affect its measurement), this screen may be removed
and a tube may be attached to divert the pump exhaust to another location. The
screen may be attached to the end of the tube with a Swagelok ® union. In most
cases the screen may simply be left in place.
4.3 Specifications
4.3.1 CO
2
/H
2
O Analyzer
CO
2
and H
2
O are measured with an LI-840A IRGA. See the LI-840A manual
(available at www.licor.com ) for specifications.
4.3.2 System Enclosure
Dimensions: 52.1 cm x 44.5 cm x 29.7 cm
(20.5 in x 17.5 in x 11.7 in)
Weight
AP200 base model: 15.9 kg (35.0 lb)
Options
IRGA: 1.0 kg (2.3 lb)
CR1000KD: 0.3 kg (0.7 lb)
CFM100/NL115: 0.2 kg (0.4 lb)
Operating Temperature: –30°C to 45°C
Power Requirement
Voltage: 10 Vdc to 16 Vdc
Power
Maximum (cold start up): 3.75 A at 12 V dc (45.0 W)
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