Pulsar DC/DC20SD User manual

1
DC/DC20SD
v.1.0
DC/DC 2A Step down DC/DC converter
with adjustable output voltage
EN**
Edition: 3 from 11.02.2016
Supercedes the edition: 2 from 15.01.2016
The module’s features:
Step down DC/DC converter with adjustable output voltage
Example of use: step down from 24V to 12V DC
The input voltage range: 8÷28V DC
The output voltage range: 4,5÷19V DC
The minimum difference between input (lowered) and output
voltage: 3V
The maximum load current 2A (24W)
The AW technical output indicating converter failure triggered
by:
Short-circuit of the output
Output overload
Protections:
Short-circuit protection SCP
Overload protection OLP
OHP overheating protection
High efficiency: 80÷90%
Optical LED indication
Warranty –2 years from the production date
Mounting:
Mounting strip with adhesive tape
Mounting screws
Example of use of the DC/DC20SD step down DC/DC converter with adjustable output voltage.
Schematic diagram of the converter operation.
Adjustment of the converter output voltage: 4,5V÷19V DC, 2A max.
1. Technical description
The step down converter DC/DC 2A (DC/DC20SD) is used for step down the input voltage from the range between 8V÷28V
DC to the voltage range of 4,5V÷24V DC at the output, adjusted with the P1 potentiometer. The maximum load current is Imax=2A
(Pmax=24W). The 3V difference between the input (lowered) and output voltage is required for the proper operation of the converter.
The module does not feature galvanic isolation between input/output (IN-AUX) and operates on common "ground" (0V) potential (IN-
and AUX- terminals are galvanically connected = common terminal).

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1.1. Block diagram (Fig.1).
Fig.1. Block diagram of the converter’s module.
1.2. Description of components and connectors (Fig. 2, Table 1, Table 2).
Table 1.
No.
[fig.2]
Component’s description
[1]
IN LED light - red
[2]
Power connector of the DC/DC module
[3]
P1 voltage adjustment (4,5÷19V)
[4]
Jumper –voltage adjustment
[5]
AUX LED light –green
[6]
The DC/DC module’s connector (power supply and AW)
[7]
AW LED light –red
[8]
Mounting strip
Table 2.
[2], [6]
Description of module’s connectors
+IN
- IN
DC supply input
(8V÷28V DC, power consumption from the power source)
+AUX
- AUX
DC supply output
(+AUX= +U, -AUX=GND)
AW
Technical output of failure: OLP/SCP activation (short-circuit or overload protection)
Failure status: hi-Z (high impedance), normal status: L (0V, GND)
Fig.2. The converter module’s view.
1.3. Technical parameters:
- Electrical parameters (Table 3)
- Mechanical parameters (Table 4)
Table 3.
The input voltage range (power supply)
8V÷28V DC
depending on the range set by the jumper
The output voltage range
4,5V÷6V, 6V÷9V, 9V÷13V, 13V÷19V
Jumper adjustable.
Factory setting: 12V.
The minimum difference between the input and
output voltage
3V

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P module power
24W max. (see fig.3)
Energy efficiency
80%÷ 90% for full range of power and loads
Ripple voltage
20mV p-p...50mV p-p
Output current
2.0A max. (See fig.3)
Current consumption by module systems
10 mA max.
Short-circuit protection SCP and overload
protection OLP
180% - 200% of module power - output power limit,
automatic return after elimination of short circuit
Technical outputs
- AW output indicating failure
- OC type, 50mA max. Failure status: hi-Z state (high
impedance), normal status: L level (0V)
Optical indication
- IN LED indicating DC power status
- AUX LED indicating DC supply status at the output
- AWLED indicating failure
- red, normal status: is lit continuously
- green, normal status: is lit continuously
- red, normal status: does not lit, failure: is lit continuously
Operating conditions
II environmental class, -10°C ÷40°C, ensure air flow around
the unit for convection cooling
Declarations, Warranties
CE, 2 years from the production date
Table 4.
Dimensions
100 x 43 x 27 (LxWxH)
Mounting
tape or mounting screw x 2
Terminals
Ф0,41÷1,63 (AWG 26-14)
Net/gross weight
0,05/0,08 kg
2. Installation.
2.1. Requirements.
The DC/DC converter is to be mounted by a qualified installer, holding relevant permits and licenses (applicable and required
for a given country) for step down installations. The module should be mounted in confined spaces with normal relative humidity
(RH=90% maximum, no condensation) and temperature range from -10°C up to +40°C. The module should operate in vertical position
in order to provide free and convectional air flow.
Proper operation of the module requires adequate current capacity of the power source; the power supply capacity should be
calculated using the formula below: PIN = 1,15 x PAUX
(PIN = 1,15 x IAUX x UAUX)
Example:
The converter will supply the receivers with a capacity of PAUX = 24W drawing a total current of IAUX = 2A at the voltage
UAUX = 24V. The minimum power supply capacity must therefore amount to: PIN = 1,15 x 2A x 12V = 27,6W.
The device should be mounted in a metal enclosure (cabinet). The rules for power supply, enclosures and shielding - according to
application - must be observed in order to meet the requirements of LVD and EMC directives.
2.2. Installation procedure.
1. Mount the enclosure (cabinet, etc.) and lead cables through cable glands.
2. Mount the DC/DC converter with adhesive tape or mounting screws.
3. Supply DC voltage to the + IN, -IN terminals with correct polarization. The supply voltage should be selected according to the table
and depending on the output voltage:
4. Switch on the DC voltage.
5. Use the jumper to set the required voltage range and adjust the required output voltage with the P1 potentiometer. Default setting:
12V.
6. Switch off the DC voltage.
7. Connect the receivers’ cables to the +AUX, -AUX connectors of the terminal block on the module’s board.
8. Connect the device cables (alarm control panel, indicator, LED light, etc.) to the AW technical output if necessary.
9. Switch on the DC voltage (the red IN LED should be permanently illuminated, the AUX green LED should be permanently
illuminated).
10. Once the tests and operation control are performed, close the enclosure, cabinet, etc.
The module's load balance should be
done prior to installation. During normal
operation, the total current of the receivers should
not exceed I=2Awhile the power drawn from the
module should not exceed Pmax=24W, as shown
in the Fig. 3.
Fig.3. The maximum output current
depending on the output voltage.
DC input voltage
DC output voltage
8÷28V
4,5÷6V
12÷28V
4,5÷9V
16÷28V
4,5÷13V
22÷28V
4,5÷19V

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3. Converter 's module operation indication.
3.1. Technical output.
The converter is equipped with three diodes indicating operation status: IN, AUX, and AW.
IN- red LED: during normal status (DC power supply) it is lit continuously. No DC supply is indicated by switching off the IN LED.
AUX- green LED: indicates DC supply status at the module’s output. During normal status, it is lit continuously, in case of short
circuit or overload the AUX led is off.
AW- red LED: indicates module’s overload. During normal status, it is off, in case of short circuit or overload the LED lights
continuously.
3.2. Technical output.
The converter is fitted with one technical output indicating failure of the DC / DC module.
AW- OLP/SCP (overload/short-circuit) output: - OC type output indicating overload/short-circuit of the module’s output.
During normal operation, the output is shorted to the AUX - (0V). In case of failure, the module disconnects the output and it is in the hi-
Z (high impedance) state during failure.
4. Maintenance and operation.
4.1. Converter overload.
The module construction is based on the modern DC/DC converter system (step-down). It features a complete short-circuit
(SCP), overload (OLP) and overheat (OHP) protection. In case of a fault or an overload of the AUX output, an automatic isolation of
output voltage occurs that is indicated by the AW LED and the AW output. After a fault or an overload is eliminated, voltage at the AUX
output recovers automatically (the module does not require reset).
5. Maintenance.
All maintenance procedures can be performed after disconnecting the converter from the power network. The converter does
not require any specific maintenance; however, its interior should be cleaned with compressed air if used in dusty conditions.
WEEE LABEL
Waste electrical and electronic equipment must not be disposed of with normal household waste.
According to the European Union WEEE Directive, waste electrical and electronic equipment should
be disposed of separately from normal household waste.
GENERAL WARRANTY CONDITIONS
1. Pulsar (manufacturer) grants a two-years quality warranty for the equipment, starting from the production date.
2. The warranty includes free-of-charge repair or replacement with an appropriate equivalent (selected by the manufacturer) if the
malfunction is due to the manufacturer. It includes manufacturing or material defects, provided that such defects have been
reported within the warranty period (point.1).
3. The equipment subjected to warranty should be brought to the place of purchase or directly to the main office of the
manufacturer.
4. The warranty applies to complete equipment, accompanied by a properly filled warranty claim with a description of the defect.
5. Should the claim be accepted, the manufacturer is obliged to provide warranty repairs, at the earliest convenience, however not
later that within 14 days from the delivery to the service centre of the manufacturer.
6. The repair period mentioned in point 5 may be prolonged, if there are no technical possibilities to carry out the repairs, or if the
equipment has been conditionally accepted, due to the breaking warranty terms by the claimant.
7. All the services are carried out at the service centre of the manufacturer, exclusively.
8. The warranty does not cover the defects of the equipment, resulting from:
- reasons beyond the manufacturer's control,
- mechanical damage,
- improper storage and transport,
- use that violates the operation manual or equipment’s intended use
- fortuitous events, including lightning discharges, power failures, fire, flood, high temperatures and chemical agents,
- improper installation and configuration (failure to follow instruction).
9. The warranty is void in case of construction changes and repairs carried out by any unauthorized service center or in case of
damage or modifications to warranty stickers and serial numbers.
10. The liability of the manufacturer towards the buyer is limited to the value of the equipment determined according to the
wholesale prices suggested by the manufacturer on the day of purchase.
11. The manufacturer takes no responsibility for the defects that result from the damaging, malfunctioning or inability to operate
the equipment especially when resulting from failure to comply with the recommendations and requirements contained in the
manual.
Pulsar
Siedlec 150, 32-744 Łapczyca, Poland
Tel. [phone], Fax. [phone]
e-mail: [e-mail], [e-mail]
http:// www.pulsar.pl, www.zasilacze.pl