Grass Valley NV7512 v.1.3 - Manual (Page 12)

2 Rev 1.3 • 10 Oct 08
1. Introduction
Power Supply
Cooling
The NV7512 frame has three fan trays. The top tray contains three fans; the side and bottom trays
contain two fans each. The fans draw cooling air from the front of the router, through the door, and
exhaust it through the rear of the frame. The router must have the door installed and closed for
proper airflow through the chassis.
Each fan features speed control so that the fan spins only fast enough to keep the temperature con-
stant within the router. Temperature sensors on the fans sense the ambient temperature and speed up
or slow down the spinning of the fan as required. By maintaining a constant temperature, circuitry
life span is increased.
Each fan features two LEDs that indicate if the fan is spinning and receiving power. For more infor-
mation, see
Indicator LEDs on page 100.
The fan trays are located at the top, bottom, and on the right side of the chassis when facing the
front of the router frame. Fan trays are readily accessed through the front of the router frame.
Filters
There are also removable air filters located on the inside of the door assembly. It is recommended
that maintenance of the fan tray and filters be performed on a regular basis. For more information,
see
Maintenance on page 99.
Power Supply
The power supply for the NV7512 is an external separate frame, the NV6257. The NV6257 uses
the NVISION PS6000 series power supply module, housing up to four primary modules and four
optional modules for redundancy. The number of PS6000 modules required depends on how many
routers are being used and the number of active cards installed.
The following lists the number of PS6000 modules required for a router with a full complement of
cards installed:
• One NV7512 — two PS6000 power supply modules (and two optional power supply modules).
• Two NV7512 routers connected together — four PS6000 power supply modules (and four
optional power supply modules).
• Three NV7512 routers connected together — two NV6257 power supply frames with one frame
containing four PS6000 power supply modules (and four optional power supply modules) and
the other frame containing two PS6000 power supply modules (and two optional power supply
modules).
• Four NV7512 routers connected together — two NV6257 power supply frames each containing
four PS6000 power supply modules (and four optional power supply modules).
The PS6000 power supply module accepts a wide range of AC input voltages and produces five
+48
VDC outputs. The power supply automatically senses the AC input voltage (90–130 and 180–
250 VAC) and adjusts to maintain a relatively constant DC output; no voltage selection is required.
Caution If airflow is impeded, overheating may occur.