UTC Fire & Security Americas Corporation Inc 785B-ALGRO User Manual

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Allegro

‰ Option 2: Hang antenna in wall (longest range).

➢ When you mark the back mounting plate’s two 

mounting holes, also mark where the antenna 
hole is (see Figure 2 for antenna wire hole loca-
tion).

➢ Where the antenna hole was marked, drill a 

hole into the wall.

➢ Remove the antenna loop (see Figure 3) from 

the panel cabinet clips and feed through the 
antenna hole and down into the wall.

‰ Option 3: Optional antenna housing (included in 

accessory pack) and attach it to the panel (medium 
range).
➢ Push the antenna housing down into the top-

right hole of the panel until it snaps into place 
(see Figure 4).

➢ Remove the antenna 

loop from the last clip 
on the panel cabinet 
and insert it into the 
antenna housing.

9.

Place panel cabinet into back 
mounting plate and snap into 
place.

Zone input is supervised using a 2k-ohm, end-of-line (EOL) 
resistor (included with panel) at the last device on the cir-
cuit. It accepts either normally open (N/O) or normally 
closed (N/C) detection devices.

The maximum loop resistance for each zone input is 300 
ohms, plus the 2k EOL resistor.

Figure 5 shows the typical wiring for N/C and N/O door/
window intrusion detection.

The panel must be powered by a plug-in stepdown trans-
former that supplies 8 VAC, 300 mA.

Connect the power transformer to the panel as shown in 
Figure 6.

Do not plug in the power transformer at this time. The panel 
must be powered up using the sequence of steps described 
in the “Powering Up the Panel” section

The panel will receive its primary power from an AC class 
II transformer. In the event of an AC power failure, the 
panel will be powered by a battery pack containing four 
rechargeable NiCd batteries. 

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