Vanguard DigiTMR S2 User Manual

Page 29

REV 1 DIGITMR S2 USER’S MANUAL

3.3.4. External Trigger Input Connections

The External Trigger Mode can be used to start recording when the DigiTMR S2 senses a voltage
(see Figure 6). This feature can be used to time a circuit breaker without using the initiate
circuit (for example, if the initiate circuit is non-operational). Another typical application for the
External Trigger Mode is to time a circuit breaker in a close operation and to start timing only
when the close coil is energized, thus bypassing the 52Y relay delay time. The DigiTMR S2 will
energize the 52Y relay to start the close operation and will then start timing when it senses the
voltage across the closing coil. Please see Figure 7 for a typical test connection. Another
application for the External Trigger Mode is to start timing the breaker when the user trips or
closes the breaker remotely.

NOTES

• Minimum trigger voltage is set at 30 Vac/dc. Maximum continuous voltage is set

at 300 Vac/dc.

• Different trigger voltages can be set at the factory based on specific user

requests.

• The DigiTMR S2 will start looking for the external trigger voltage when the

message “AWAITING TRIGGER…” is shown on the LCD. If the external trigger
voltage is not sensed by the DigiTMR S2 within ten seconds after the initiate
sequence has begun, the DigiTMR S2 will return to the main menu.

Figure 6. External Trigger Cable Connection for an Open Connection