Lucent Technologies -48V CPS4000/CPS4000 PLUS Cabinet Power System
Issue 13 December 2000
Alarms, Controls, and Displays 7 - 23
LVD/Thermal Management, continued
EURO Mode
Algorithm
•
As temperature rises between 20°C (68°F) and 53°C (127°F), plant
voltage is lowered 72mV per degree.
•
As the temperature decreases below 20°C (68°F), the plant voltage
increases at the same rate of 72mV per degree until it reaches a
maximum of 56.7 volts.
•
For temperatures between 53°C (127°F) and 75°C (167°F), the
plant voltage depends upon the plant set voltage. If the plant set
voltage is between 52 and 54.5, the voltage will be at two volts less
than the uncompensated battery float voltage. If the plant set
voltage is between 54.5 and 55, the plant voltage will be
determined by the formula: V
min
= 121.125 - 1.25 * V
set
•
For temperatures higher than 75°C (167°F), the plant voltage is
reduced to approximately 47.5 volts to protect against thermal
runaway. The 48-volt plant setting will stay in effect until the
battery temperature drops to 65°C (149°F), where thermal
compensation resumes normal operation.
ES648 MCUs provide the switch-selectable EURO Mode thermal
management option (illustrated in Figure 7-3), with the NAFTA Mode
the factory-set standard.
Figure 7-3: -48V Slope Temperature Compensation
EURO Mode Algorithm
