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Option11C and 11C Mini TechnicalReference Guide
Over-voltage
An OVP (Over-Voltage Protection) circuit will shut down the power supply
if the output voltage exceeds the limits given in Table62.
All outputs in a shutdown state are reset by the SSC card.
The system power will not automatically reset when there is overvoltage on
the -52V DC output. Manual intervention is required. The manual int button
is located on the faceplate of the SSC card.
Temperature sensor
The power supplies a re sensitive to the temperature of the cabinet and the
system power. A thermost at is located at the to p of the power suppl y unit. The
AC or DC input breaker will be tripped for temperatures higher than 80°C
(176°F).
Reserve power LED
The NTAK04 and NTDK78 AC/DC power supplies oversee the status of the
reserve power system. When the breaker on the NTAK28, NTAK75, or
NTAK76 breaker assembly trips, the “Batt” LED on the NTAK04or
NTDK78 faceplate is turned off.
Table 6 2
Nominal and over-voltage limits of NTAK04, NTAK05, NTDK72 and NTDK78 power supplies
Nominal voltage Overvoltage limit Power supply status
+5.1V +6.4V Complete Shutdown
+8.5V +10.6V Complete Shutdown
-150V -187.5V Complete Shutdown
+15V +18.7V Complete Shutdown
-15V -18.7V Complete Shutdown
-48V N/A N/A
Ring (Pk V) 150V Complete Shutdown
-52V -58V Complete Shutdown