Chapter 1 - Product Specifications
13
© 2017 Geist
GM1118 Watchdog 100 Instruction Manual
NOTE
This sensor may be heated by internal circuitry in the unit; a
temperature offset is available to re-calibrate.
·
Humidity:
Measures the percent of water vapor in the air /- 2% accuracy
within a range from 20% to 80%.
·
Dew Point
: The atmospheric temperature, based on pressure and humidity,
below which moisture in the air begins to condense and form dew.
·
AI1:
Scales 0 to 5 Vdc input to 0-99, dry contacts may be used.
·
AI2:
Scales 0 to 5 Vdc input to 0-99, dry contacts may be used.
·
AI3:
Scales 0 to 5 Vdc input to 0-99, dry contacts may be used.
·
AI4:
Scales 0 to 5 Vdc input to 0-99, dry contacts may be used.
Figure 1-2
Watchdog 100-P
Analog I/O Sensors
The Watchdog 100 units come equipped with four Analog I/O ports for connecting
additional external sensors such as Flood and Door Sensors. The four ports are
designed to accept a 0-5 Vdc analog input; alternatively, an internal 100K pull up
resistor to 5 V allows for the use of dry contacts. The Analog I/O port input is
converted to a digital number ranging from 0 to 99 and is displayed on the Sensors
page. Unused I/O ports will display a value of 99. This range can be adjusted on the
display page allowing the user to modify the value to make it more meaningful to the
user.
Flood sensors act as conductivity bridges. Moisture across the contacts causes the
value to drop. Door switches can be wired in a serial connection; if the chain is broken
the entire group is classified as open. The limiting factor on the I/O ports is the length
of the wire, found to be around 400 feet.
