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Installation Instructions
Loop Detector
Models A200 and A201
Figure 1. A200 3M stock number Figure 2. A201 3M stock number
78-9236-6456-5 78-9236-6498-7
Introduction
These instructions explain how to install and configure the 3M Models A200 and A201 Loop Detectors as part of
a Drive-thru Vehicle Detection System. With the exception of mounting, both circuit boards are the same.
The Model A200 Loop Detector comes with a 12VDC plug-in power supply and is designed as a stand-alone
loop detector. Use this detector if a backup wired intercom is used to support the primary intercom.
The Model A201 Loop Detector comes with a special ribbon cable and is designed specifically as an optional
accessory for the 3M C921BA or later Base Station. Power and switch closure signals are supplied through a
ribbon cable.
Use these detectors with either the 3M Prefab Loop Kit (3M stock number 78-8016-9901-4) for new driveway
construction, or with the 3M Saw-In Loop Kit (3M stock number 78-8016-9813-1) for existing driveways.
Install the appropriate magnetic loop kit first, following instructions enclosed with that kit. Then install a 3M
Combination Duplex Cable (3M stock number 78-8095-0180-8) or other 18-gauge, shielded, twisted-pair,
jacketed cable between the menu sign and the drive-thru intercom location inside the building.
WARNING: Do not route Speaker/Mic or Loop cables through the same conduit with 115 VAC
electrical wiring. This violates the National Electrical Code and presents a safety hazard.