LMU-4200™ Hardware and Installation Guide
V1.0.9
November 13, 2010
Copyright ©CalAmp DataCom Inc 2010
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CalAmp Proprietary & Confidential
2.4.2
3-Axis Accelerometer Input
The LMU-4200™ supports an internal 3 Axis Precision Accelerometer as one of its discreet
inputs. When the LMU is moved in any direction, the associated input will be in the High
state. If the LMU’s accelerometer does not detect motion, then the input will be in the Low
state. No external connections are required for this functionality to be operational.
2.4.3
Outputs
The LMU’s and ioPOD;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 12 - Sample Relay Wiring