Grass Valley NV7512 v.1.3 - Manual (Page 110)

100 Rev 1.3 • 10 Oct 08
6. Maintenance
Fuse Replacement
9 Verify that one or both AC cords are firmly seated at both ends. Make sure that the spring bail
power cord retainers on the rear of the frame are in place.
Fuse Replacement
If a problem occurs on a card, the first thing to do is check the fuses.
Fuses are located on each of the router’s active cards. Each card features either a “fast blow” or a
fuse that can be reset (“slow blow”). If the card requires a large amount of power, the fuse is “fast
blow” and must be replaced if blown. If the fuse can be reset, reset the fuse by removing the card
from the frame and letting the card temperature cool down. When the fuse temperature reduces to a
safe operating temperature, the fuse automatically resets itself and the card can be reinstalled. The
following table lists the fuses on each card:
Indicator LEDs
Indicator LEDs indicate whether AC power is present and if a card is operating normally. All
LEDs, except for those on fans, are visible when the router front door is closed. In the following
sections, LEDs are listed in the order they appear on the cards, from top to bottom.
Indicator LEDs on Power Supplies
The five green LEDs on the front of the power supply modules indicate presence of the five +48
VDC outputs of the five branch circuits. All five LEDs should be lit at all times when AC power is
present. If any LED is off, either the power supply has failed or the branch circuit is shorted.
Card or Module Fuse Value
Power supply AC Line Fuse 8 Amp, 5 × 20 mm, Slow Blow
Control card 1 Amp, Fast Blow
Crosspoint card 1 Amp, Fast Blow
Input card 1 Amp, reset
Output card 1 Amp, reset
Monitor card 1 Amp, reset
Warning Dangerous voltages are present at the rear AC power connector and on the power
supply module. Take precautions to prevent electric shock: Do not touch exposed
wires or connecting pins.