Grass Valley NV7512 v.1.3 - Manual (Page 30)

20 Rev 1.3 • 10 Oct 08
1. Introduction
Active Cards
The router alarm connection is labeled ‘ALARM’, as shown in Figure 1-15. For instructions on
making alarm connections, see
Making Alarm Connections on page 71.
Figure 1-15. Alarms Connection (Rear View)
Active Cards
The NV7512 features several active cards that manage incoming signals, forward commands from
the router control system, perform signal switching, and distribute outgoing signals. Each card
slides into a card guide and has a two levers that aid card ejection.
There are:
• 2 control cards (one primary, one secondary - optional for redundancy)
• Up to 16 input cards
• Up to 16 output cards
• Up to 4 crosspoint cards
• 1 monitor card (optional)
Each card and function is described in the proceeding sections. For information on installing cards,
see
Installing Active Cards on page 42.
Control Cards
The router has two control cards (EM0374), one primary and one secondary (optional for redun-
dancy). A control card receives commands from the router control system, and in turn, controls the
input, output, crosspoint and monitor cards.
Both the primary control card and the secondary control card receive router control system com-
mands, but only the primary control card actively sends commands to the crosspoint cards. Because
both cards receive router control system commands, if the active (primary) control card fails, the
back-up (secondary) control card automatically and seamlessly takes over processing. In addition,
the primary control card and secondary control card communicate with each other. Should either
control card fail, the now active control card communicates the failure to the router control system.
The control card also monitors taxometers on the fans, which indicate if the fan is spinning or not.
The control card forwards this information to the router control system for monitoring.
The control card includes a status reporting circuit. Four LEDs on the front of the control card indi-
cate the card’s status: low battery (Red), alarm (Red), active (Amber) and operating normally
(Green). For more information, see
Indicator LEDs on page 100.
Input Cards
The router frame can house up to 16 input cards, each processing up to 32 signals, depending on the
card. Input cards receive incoming signals through passive coaxial connectors on backplanes. (See
Backplanes on page 12.) There are three types of input cards managing different signal formats.
ALARMS
System Alarm
Connection