Miranda NV5100MC Master Control, Справочное руководство

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NV5100MC Master Control • Reference Man ual 27
3. Frames
Connectors
Figures 3-5 and 3-6 show sample system-level alarm circuits. (You can use alarm signalling
devices other than LEDs, or in addition to LEDs.)
Figure 3 -5. Simple Alarm Circuit
Here, LEDs are all off unless a failure occurs. The LED for the failed circuit turns on .
This is an alarm circuit that can drive heavier loads, not just LEDs.
Figure 3 -6. Alarm Circuit to Drive Loads
In this example, the LEDs are normally on and turn off when a failure occurs.
CAUTION: If the alarm load is inductive, protect the internal alarm relay contacts with a reversed-
biased diode. The external supply voltage should not exceed ±30VDC and the load resistors should
be sized to limit contact current to less than 150mA.
Power Supply Alarms
At the lower right portion of the rear of the frame is a Phoenix 3-pin connector for power supply
alarms:
The frame 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.
1
COM
Current flows between contacts
during internal alarm condition
Normally off, the LEDs
turn on to indicate failure
Customer’s Power,
30VDC max, 150mA max
Customer’s Ground
Customer’s Power,
30VDC max, 150mA max
Customer-supplied relay
contacts closed during normal
operation, open during alarm
Current flows between contacts
during internal alarm condition
Normally on, the lamp turns
off to indicate failure.
1
COM
Customer’s Ground