SPETCREX INC
SafEye
™
™
Series 200 IR Gas Detector - User’s and Maintenance Manual
Doc. No. TM792100, Rev. B, Oct..1997
- 34 -
2. 5. Detector Wiring
This section does not attempt to cover all of the standard practices and codes of
installation. It emphasizes specific points providing the basic concept for qualified
wiring installation personnel.
Warning!
Do not separate or close the housing section from the cover
while the power is at “on” position.
Caution!
It is very important that the Cover and Housing sections be
exposed to the environment for the least amount of time due to
the internal circuitry. Proper planning of the wiring is
required in order to reduce the amount of time the Cover and
Housing sections are apart.
2. 5. 1.
Pre-Wiring Requirements
The following instructions are applicable for both the Source unit and the Detector
unit.
Use color coded conductors or suitable wire markings or labels. Use 12 to 20 AWG
wires for site wiring. The selection of wire gauge should be based on the distances
between the power supply and the Flash Source and the power supply to the Detector
units.
Procedure for Selecting the Wire Gauge:
1.
Determine the wire length for each of the units.
2.
Determine the wire gauge by calculating the voltage drop in respect to the wire
length and gauge for each unit (see Table 2-3). Insure that the units will receive
a minimum of 18 volts DC at the terminal contact points and not exceed 32
Volts DC.
3.
The appropriate cable should be shielded.
Table 2-3. Maximum DC Resistance for Copper Wire
AWG #
mm
2
Ohm/100m
20
0.51 - 0.61
3.5
18
0.81 - 0.96
2.2
16
1.22 - 1.43
1.4
14
1.94 - 2.28
0.88
12
3.09 - 3.40
0.55
The conduit should be installed in accordance with the unit's location and the local
conduit codes for installation procedures.
