10/12/13
TTU-12x0 Hardware & Installation Guide - PULS Wiki
https://puls.calamp.com/wiki/TTU-12x0_Hardware_%26_Installation_Guide
12/36
Sample Input Wiring
3.5.6 Outputs
The TTU’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.
Sample Relay Wiring
External vs Internal Power Switch
This output allows the TTU to switch between power sources when certain conditions are met (e.g. low power on the
currently selected supply). If this output is set then the TTU will use its internal battery as its power supply. If this output is
cleared, the TTU will use the external power supply.
By default, this output is cleared so the TTU-12x0™ will operate off external power.
Enable / Disable Battery Charging
This output allows the TTU to enable or disable the charging of its internal battery. If this output is set then the TTU will stop
charging the internal battery. If this output is cleared, the TTU will charge the internal battery.
By default, this output is cleared (i.e. battery charging enabled)
3.5.7 Status LEDs
The TTU-12x0™ is equipped with two Status LEDs, one for GPS and one for COMM (wireless network status). The LEDs
use the following blink patterns to indicate service:
LED #1 (Comm LED - Orange) Definitions
