C O R P O R A T I O N
TPCMQ DC/DC CONVERTER SERIES
OPERATING MANUAL
10
12.0 OPERATING INFORMATION
12.1 Input
Voltage.
The TPCMQ Series converters operate off DC input volt-
ages within the range of 40 to 60 or 20 to 30VDC. There is a separate
input connection for each converter module to bus bars at the rear of the
rack/shelf. For complete details see Section 17.2 and Figure 4.
12.2 Output Connection.
The DC output of the rack/shelf is provided at two
copper bus bars. Each bus bar has a no. ¼-20 stud and nut for the output
connections. For complete details see Section 17.3 and Figure 4. Both
positive and negative outputs are fl oating and isolated from the chassis.
12.3 Output Voltage.
The output voltage of each converter module is factory
set to its specifi ed voltage. This voltage can be adjusted in two ways. First,
there is a V adjust potentiometer at the top of the module case. See Figure
3. This adjustment has a range of approximately ±5% for the TPCMQ48
and ±4% for the TPCMQ24.
Second, there is a wide-range adjustment of approximately -25% to +10%
by means of the Remote Adjust input to each converter module. This is
found at pin 16 of the TPCMQ48 and pin 29 of the TPCMQ24. On the
rack/shelf the Remote adjust is found at J4 pins 12, 24 & 25 for each
module. A zero to +5V input to these pins adjusts the output from -25% to
+10%. An input voltage of +2.5V, or an open, gives the factory-set voltage
at the output. The output voltage can actually go above +10%, but this
could trip the overvoltage protection (OVP) circuit.
All three converter modules in a rack/shelf can be controlled from a single
analog control voltage by connecting J4 pins 12, 24 & 25 together.
12.4 Output Power.
Maximum output power for the TPCMQ48 modules is 700
watts for the 24 or 27.2V output models and 650 watts for the 12 or 13.6V
models. The maximum output power for the TPCMQ24 modules is 1,000
watts. The maximum output power of a module may be drawn at up to
50
o
C ambient temperature. Above 50
o
C the output current must be derat-
ed by 2.5%/
o
C. See Fig. 5. The maximum operating temperature is 70
o
C,
at which the output current must be derated by 50%.
12.5 Output Overload Protection.
Each converter module output is protected
from damage due to overload or short circuit conditions. This protection is
continuous and without damage; recovery is automatic when the load is
removed. Current limiting takes place at approximately 105% of the rated
output current.
