Input; Ac Input Line Requirements; Dc Output; Output Voltages - TDK-Lambda CPFE500 Application Note

1. INPUT

AC INPUT LINE REQUIREMENTS

See datasheet for specification of input line requirements (including Input voltage range, Input frequency, Input
harmonics, Input current and leakage current)
The power supply will automatically recover from AC power loss and shall be capable of start-up under peak
loading at 85VAC.
Repetitive ON/OFF cycling of the AC input voltage shall not damage the power supply or cause the input fuse to
blow.
Input Fuse
•
Not user serviceable. Fast Acting, high breaking capacity, ceramic fuse, 15A/250V rated
Input undervoltage
•
The power supply is not designed to be protected against the permanent application of an input voltage
below the minimum specified. Avoid or protect against input undervoltage conditions that exceed 30seconds
duration.

2. DC OUTPUT

OUTPUT VOLTAGES

Output voltages are factory set at 12V, 24V, 28V or 48V +/-2% depending on the model.
The output voltage may be subsequently adjusted using the potentiometer 'R3' within the ranges listed below :-
12V model 9.6V ~ 14.4V
24V model 22.4V ~ 33.6V
28V model 22.4V ~ 33.6V
48V model 38.4V ~ 57.6V
On models fitted with output OR-ing diode, the maximum voltage shown above will be the voltage before the
OR-ing diode. The maximum adjustment voltage after the OR-ing diode will subsequently be reduced by up to
1V.
The main output voltage, auxiliary output voltage and output signals are isolated from the baseplate but not
isolated from each other. The remote on/off control is isolated from all outputs and baseplate.

REMOTE SENSE

Remote sensing, if required, can be connnected via the control signal connectors J2,J3 (pins 1 & 2) and
compensates for both +Ve and –Ve power line voltage drop. The remote sense terminals are internally
connected to +ve and -ve outputs via 100R/0.25W resistors and maybe left unconnected if not required. On
models fitted with output OR-ing diode, the internal connection is before the diode.
When using remote sense, the maximum power cable voltage drop should be limited to :-
+Ve Power cable
-Ve Power cable

OUTPUT OR-ING DIODE

CPFE500 series PSU maybe specified with or without integral OR-ing diode.
For models with OR-ing diode, the diode is fitted in the +ve output terminal of the PSU.
On 12V,24V & 28V models, the OR-ing diode is a schottky type rectifier.
On 48V models, the OR-ing diode is an ultrafast type standard rectifier.
CPFE500F Application Note
1.5V max (includes OR-ing diode drop on models fitted with OR-ing diode)
0.5V max
Document Number : 61066 iss 2 Page 3 of 17