D150-05-00 REV #: 003
2
I56-1028-000
ate correctly if system components have incompatible
allowable loop resistances.Therefore, before beginning
installation, refer to the control panel manufacturer’s loop
resistance specification to ensure that it is listed as com
-
patible with the System Sensor base and smoke detector
being installed.
Connect detectors only to ULC compatible control units.
All wiring must be installed in compliance with the National
Electrical Code and all applicable local codes and any spe-
cial requirements of the authority having jurisdiction, us-
ing the proper wire size. The conductors used to connect
smoke detectors to control panels and accessory devices
should be color-coded to reduce the likelihood of wiring
errors. Improper connections can prevent a system from
responding properly in the event of a fire.
For signal wiring (the wiring between interconnected de-
tectors), it is recommended that the wire be no smaller
than AWG 18. However, the screws and clamping plate
in the base can accommodate wire sizes up to AWG 12.
The use of twisted pair wiring for the power (+ and -) loop
is recommended to minimize the effects of electrical inter-
ference.
NOTE:
To ensure that electrical connections are super-
vised, do NOT loop wires under terminals 2, 3, and
5 - break the wire at each terminal.
To make electrical connections, strip approximately 3/8" (1
cm) insulation from the end of each wire. Slide the wires
under the clamp plate and tighten the terminal screw.
Check the zone wiring before installing the smoke detec-
tor head. The built-in shorting spring makes it convenient
to do this. After the detector base is wired and attached to
the electrical box, position the shorting spring against ter-
minal 3. Use the slot in the retaining clip to hold the spring
against the terminal, as shown in Figure 1. This shorts the
negative-in and negative-out leads so that loop wiring can
be tested for continuity.
The shorting spring in the base will disengage automati-
cally when the detector head is removed from the base.
DO NOT remove the shorting spring since it reengages as
the detector head is turned into the base, completing the
circuit.
Tamper-resistance Feature
NOTE:
DO NOT use the tamper-resistance feature if the
System Sensor XR2 Removal Tool will be used to
remove detectors from the base.
This detector base can be made tamper resistant so that
the detector cannot be detached without the use of a tool.
To make the base tamper-resistant, break off the smaller
tab at the scribed line on the tamper-resistance tab, on the
detector mounting bracket (see Figure 3A), before install-
ing the detector.
To remove the detector from the base after it has been
made tamper resistant, remove the decorative ring by
rotating it in either direction and pulling it away from the
base.
Then, insert a small screwdriver into the notch (see Fig-
ure 3B), and press the plastic lever toward the mounting
surface before rotating the detector counterclockwise for
removal.
SNAP ON
DECORATIVE
RING
SCREWS (NOT
SUPPLIED)
DETECTOR
BASE
BOX (NOT
SUPPLIED)
SHORTING
SPRING
Figure 1. Mounting base to box:
A78-1175-01
