Studer SW V4.0 OnAir 1000 Operating And Service Instructions page 177

Alarm Output
Pin Assignment
4
Date printed: 24.10.03
Power alarm is triggered if the internal or external supply voltage drops
below 23.0 V; then the POWER ALARM LED on the front panel is
illuminated, and a power alarm signal is output on pin 4 of the DC supply
connector.
The power alarm signal is a relay contact (max. 40 V/200 mA). Its
behaviour depends on jumper J1 on the PSU sub board (see component
layout diagram above); either pin 4 is normally floating and pulled to GND
if alarm is active (P1 and P2 connected, default factory setting), or pin 4 is
normally pulled to GND and becomes floating if alarm is active (P1 and
P3 connected).
Should the supply voltage drop below 21.6 V, the console automatically
shuts down after having stored all relevant data.
For correct start of the console a supply voltage of min. 22.0 V is required.
24 V DC connector (10pin, male)
Matching female connector: Hirose JR21PK-10S, order no. 54.20.2010
Pin Signal
1 +22...28 V
2 +22...28 V
3 +22...28 V
1 2 3
4 Power alarm output (see "Alarm Output" above)
5 Power supply select 2 (see "Wiring" above)
7
6 Power supply select 1 (see "Wiring" above)
8 9 10
7 GND
8 GND
9 GND
10 GND
SW V4.0
OnAir 1000 Digital Mixing Console
DC
DC
DC
Hardware 2-7