Samlexpower SDC-20 Owner's Manual

Non Isolated DC TO DC Converter SDC-20
(For use in hazardous locations - Class 1, Div. 2, Gp. C & D, T6)
WARNINGS!
- This unit is not a battery charger! Hence, do not connect this unit directly to a
battery for battery charging purposes
- This unit is designed to be used on negative grounded systems only. Do not
connect the input / output sides to a positive grounded system
- The input and output sides have a common negative ground. Hence, there is no
isolation between the input and the output sides
BATTERY +24VDC NOMINAL
BATTERY GROUND
DESCRIPTION
SDC- 20 is a non isolated DC to DC converter that converts 24 VDC nominal voltage (range 20
VDC to 35 VDC) to 12 VDC nominal voltage (13.8 VDC). The input and output sides have a com-
mon negative ground. Hence, there is no isolation between the input and the output sides. Both
the input and output sides are isolated from the chassis of the unit.
The unit is designed to be operated in hazardous envirionment - Class 1, Div 2, Gp. C& D, T6
PROTECTIONS
Overload / Short Circuit: The unit is protected against overload by current limiting. When the
output current reaches the current limit value (please see the specs), the output voltage will drop
and will no longer be regulated. The unit will reset automatically once the overload condition is
removed.
Temperature Compensated Current Limit: As the temperature of the main switching MOSFET
increases, the value of the current limit decreases.
Over Voltage on the Output Side: If the output voltage increases beyond 16.5 V +/-0.5 V, a crowbar
circuit will activate and blow the input side fuse.
Over Voltage / Transients on the Input Side: The input side is protected against over voltage and
transients through a Transient Voltage Suppressor. In case the input voltage exceeds 37 VDC, the
internal fuse will blow.
Reversal of Polarity on the Input Side: In case the input side polarity is reversed, the external input
side fuse will blow.
OWNER'S MANUAL
IN IN OUT
+24V GND GND
+ - -
1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7
1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7
1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7
1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7
OUT
+13.8V
+
LOAD +12VDC NOMINAL(13.8V)
LOAD GROUND