Daikin MicroTech II User Manual

www.DaikinApplied.com 41 OM 752-4
dIaGnostICs and serVICe
Troubleshooting Humidity Sensors
The UVC is congured to use a 0–100% RH, 0–5 VDC, capacitive humidity sensor.
Each sensor is calibrated according to the table shown.
CAUTION
The humidity sensor is not protected against reversed polarity. Check carefully when connecting the
device or damage can result.
Use the following procedure to troubleshoot a suspect sensor:
1. Disconnect the sensors output voltage lead from the UVC analog input.
2. Using some other calibrated humidity sensing device, take a humidity reading at the
sensor location.
3. Use the humidity reading from Step 2 determine the expected sensor voltage from
Table 23.
4. Using a calibrated multi-meter, measure the actual voltage across the yellow and
white sensor leads.
Wire color denitions:
White = ground
Yellow = output VDC
Blue = supply VDC
5. Compare the expected voltage to the actual voltage.
6. If the actual voltage value deviates substantially (more than 10%) from the expected
voltage, replace the sensor.
Table 23: Humidity versus voltage
RH (%) VDC (mV) RH (%) VDC (mV)
10 1330 55 2480
15 1475 60 2600
20 1610 65 2730
25 1740 70 2860
30 1870 75 2980
35 1995 80 3115
40 2120 85 3250
45 2235 90 3390
50 2360 95 3530
Troubleshooting Carbon Dioxide (CO
2
) Sensors
The UVC is congured to use a 0–2000 PPM, 0–10 VDC, single beam absorption infra-
red gas sensor. Each sensor is calibrated according to the table shown.
Use the following procedure to troubleshoot a suspect sensor.
1. Disconnect the sensors output voltage lead from the UVC analog input (xAI-3).
2. Using some other calibrated CO
2
sensing device, take a CO
2
reading at the sensor
location.
3. Use the CO
2
reading from Step 2 to determine the expected sensor voltage from
Table 24 on page 42.
4. Using a calibrated multi-meter, measure the actual voltage across the lead removed
from xAI-3 and ground.
5. Compare the expected voltage to the actual voltage.
6. If the actual voltage value deviates substantially (more than 10%) from the expected
voltage, replace the sensor.
In the unlikely event that the CO
2
sensor requires calibration, consult the factory for
information on obtaining calibration equipment and instructions.

Daikin MicroTech II Specifications

General

Brand	Daikin
Model	MicroTech II
Category	Controller
Language	English