Grass Valley NV5256 v.1.8 - Manual (Page 26)

18 Rev 1.8 • 08 Jul 11
3. Detail
Power
Power Supply Alarms
At the lower right portion of the rear of the NV5256 frame is a Phoenix 3-pin connector for power
supply alarms:
The NV5256 has alarm outputs for each power supply installed in the frame. An internal solid-state
relay is provided for each supply. The relay turns on when there is an alarm condition.
Figure 3-3 shows suggested alarm circuit implementations. You can use signalling devices other
than LEDs or in addition to LEDs. For example, you can operate a buzzer or other audible alarm to
warn operators of a potential problem.
Figure 3-3. Power Supply Alarms
CAUTION: The voltage of the external power supply for alarm signalling should not exceed
±30VDC. Resistors should be sized to limit the current through each internal alarm contact to less
than 150mA.
If the load is inductive, the alarm contacts should be protected with a parallel, reverse-biased diode.
Power
The NV5256 has two power supply bays (and two power connectors) to support redundancy. Only
one power supply is actually required.
PS ALARMS
1 2 COM
NORMALLY
CLOSED
E146905
90-130/180-250V~
7.5A/3.75A
50/60Hz
660 WATTS MAX
TO REDUCE THE RISK
OF ELECTRIC SHOCK,
DISCONNECT TWO
POWER SUPPLY CORDS
BEFORE SERVICING.
113-128
8
97-112
7
81-96
6
65-80
5
49-64
4
33-48
3
17-32
2
1-16
1
145-160
10
161-176
11
92 129-144
9
PORTS
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16
13-16
PORT 16 6
PS Alarm
Connector
1 2
1 2
CO
COM
Customer-supplied relay
contacts NC (and closed
during normal operation)
Extermal Power,
30VDC max, 150mA max
Normally on, the
LEDs turn off to
indicate failure
Normally off, the
LEDs turn on to
indicate failure
External Power
30VDC max, 150mA max
Internal alarm signals
normally clear, controlled
by software
Internal alarm signals
normally clear, controlled
by software