5
WatchDog model 200, 225, 400, 425, and 450 loggers have
external channels (ports) for external sensor input. The following
table lists the available optional sensors. Most sensors include a 6-
foot cable with pin-type connector. Items 3667-20 and 6450WD20
have 20 foot cables.
Item #
Description
Measurement
Range
Accuracy
3665R
Tipping Bucket Rain
collector
N/A
±2%
3666
Leaf Wetness Sensor
0(Dry) - 15(Wet)
N/A
3667
3667-20
External (Soil)
Temperature Sensor
-30° to 100°C
-22° to 212° F
±0.6°C
±1°F
3670
Silicon Pyranometer
1-1250 W/m
2
±5%
3668
Quantum Light Sensor
0-2500 umol m
-2
s
-1
±5%
3669
3669LT
Soil Moisture
Transducer
0-100 kPa
±2%
6450WD
6450WD20
Watermark Soil Moisture
Sensor
0 - 200 cbars
N/A
6451
Irrigation Sensor
Switches at 5 psi
±1 psi
3673
3674
Input Cable for user-
supplied
sensor
0-2.5V
4-20mA
N/A
External Sensors
To connect the external sensor to the logger, plug the data cable
into the logger port that has been programmed for that particular
sensor. If the sensor is not connected, a “- - -” will appear on the
LCD display for the respective logger port until the sensor is
connected.
Port A is the only channel that will record rainfall data
Program each channel (port) to a specific sensor through the
SpecWare launch screen. Refer to the
SpecWare Software
User’s Guide
for more detailed instructions on launching and
sensor configuration.
