Extech Instruments K.J.E.T. 422324 Instruction Manual page 9

9. High / Low Alarm output connector
Fig-4
Pin 1: GND ( external supply low voltage )
Pin 2: VCC ( external supply high voltage )
Pin 3: SYNC ( external trigger signal )
Pin4 (High Alarm) and pin5 (Low Alarm) signals must be
synchronized with pin3. Pin5 and pin4 will not function
(always low) unless SYNC (pin3) is high. If SYNC is low, then
pin4 and pin5 will be low.
1
Pin4 : High Alarm
If the reading is higher than the high alarm setpoint, then (pin 4)
will be high, otherwise, it will be low.
1
Pin 5 : Low Alarm
If the reading is less than or equal to the low alarm limit, (pin 5)
will go high.
1
The Pin 4 and 5 outputs may be delayed 0.4 seconds due to the
datalogger's A/D scanning time.
Description of the DIN cable:
Red wire
Black wire GND (external supply low voltage)
Yellow
White
Purple
VCC (external supply high voltage)
SYNC (external trigger signal)
High Alarm
Low Alarm