Sensaphone 1800 - Manual (Page 29)

Chapter 2: Installation
27
terminal. For recommended thermistors check the accessory list
or thermistor data in the appendices. Temperature range for 2.8K
thermistors is -109° to 115°F (-85° to to 57°C). The temperature
range for 10K thermistors is -87° to 168°F (-66° to 76°C)
Dry Contacts: Only contacts which have no voltage or current
applied may be used. Connect the contact to a Zone terminal and
an adjacent ground terminal. Do NOT try to monitor a contact that
switches 120VAC. This will permanently damage the unit.
4–20mA: A 4–20mA transducer requires you to have an external
DC power supply for the transducer. Connect the positive wire of
your transducer to the positive terminal of your DC power supply.
Connect the negative terminal of the transducer to a Zone terminal
on the Sensaphone 1800. Connect the negative terminal from your
power supply to the adjacent ground terminal on the 1800.
+ -
Z O N E
1
+ -
Z O N E
2
+ -
Z O N E
1
+ -
Z O N E
2
+ -
Z O N E
1
+ -
Z O N E
2
4–20mA Transducer
Dry Contact
Input Zones
Terminal Strip
Dry Contact Sensor
NO/NC
Input Zones
Terminal Strip
Temperature Sensor
Thermistor
Input Zones
Terminal Strip
External Power Source
4-20mA transducer
VDC
4–20MA
Figure 5: Different Sensor Types connected to the Terminal Block
Wiring Recommendations
The 1800 will work fine in indoor environments using unshielded
cable. When wiring will be subject to long lengths (>250') or if run
outdoors, it is highly recommended that shielded cable be used and
that the shield be connected to an earth ground. Also, be sure to use
the appropriate gauge wire based on the distance and sensor type.
See chart below:
Wire Gauge Thermistor NO/NC Contact & 4–20mA
#24 250' 1000'
#22 500' 2000'
#20 1000' 4000'