User's Guide

- 30 - CalAmp Proprietary & Confidential
6.1.2 Outputs
The LMU‘s outputs are designed to drive external relays. These outputs provide a high-
current, open-collector driver that can sink up to 150 mA each. These drivers may be used to
drive external relays that can then control vehicle functions such as door locks, fuel shut-off
valves, sirens and lights. If additional current is required to drive the relays, external circuitry
can be added to source the current. This diagram is a typical use of an output to drive a relay.
Vehicle Power
(+12VDC)
Relay
Coil
Relay
Contacts
Relay
Ground
LMU
85
86 87
30
Output 0
Figure 7 - Sample Relay Wiring