Longwei Electric LW1510KD User manual

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Warning: Do not connect any load to the power supply before it's turned on.
Likewise, make sure to disconnect the load before shutting down the power
supply. Damages to the power supply can happen if you do not follow this.
Such damages are not under warranty.
Warning: If you are running inductive load like magnetic coils, DC motors,
stepper motors, etc., make sure to change the voltage/current slowly, and
NEVER turn the power supply on or off with a inductive load connected!
I Summary
This serial single output switch power supply is a kind of DC regulated
power supply.
It has high efficiency, stronger load ability, and long continuous working
period characteristics. Also it has perfect over voltage, over temperature,
overload protection functions and so on. It can act as constant voltage as well
as constant current DC power supply. This series of power supplies are first
choices for scientific and research institutions, colleges, factories units ect.
See the models from the table1.

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Single output switch power supply
(Table 1)
II Panel’s characteristics and technical parameters
2.1 Panel’s characteristics
(1) Digital ammeter: display the output current value
(2) output positive terminal: the anode of the output voltage connects to
positive terminal of the load.（Attention: the maximum output current of
the front output terminal is 10A, if the output current is more than
10A, please choose the back output terminal）
(3)Cabinet ground terminal: the cabinet connects to the ground.
(4)output negative terminal: the negative electrode of output voltage connects
to the negative terminal of the load. （Attention: the maximum output
current of the front output terminal is 10A, if the output current is
more than 10A, please choose the back output terminal）
Model
Output
Voltage
Output
Current
Display
Display
Accuracy
LW1510KD 0~15V 0~10A 3LED display ±1%±1 digit
LW1520KD 0~15V 0~20A 3LED display ±1%±1 digit
LW1530KD 0~15V 0~30A 3LED display ±1%±1 digit
LW3010KD 0-30V 0-10A 3LED display ±1%±1 digit
LW3020KD 0-30V 0-20A 3LED display ±1%±1 digit
LW3030KD 0-30V 0-30A 3LED display ±1%±1 digit

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(5)Power switch when the power switch is placed “ON” Conversely, the
machine is off.
(6)Constant-current setting knob: regulate the knob to set the max current
value or constant current value.
(7)Digital voltmeter: Display the output voltage value.
(8)Voltage regulation output voltage adjusting knob: regulate the output
voltage value.
(9)Voltage regulation indicator light: when the power supply is under the
condition of voltage regulation, the indicator light is on.
(10) Current regulation indicator light: when the power supply is under the
condition of current regulation, the indicator light is on.

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2.2 Rated operating condition
(1) Input voltage: AC220V±10% 50Hz or AC110V±10% 60Hz
(2) Working conditions: -100C -400C relative humidity<90%
(3) Storage conditions: -200C-800C relative humidity<80%
2.3 technical parameters
(1) Voltage stabilization: ≤0.5%
(2) Current stabilization: ≤0.8%
(3) Load stabilization: ≤0.5%
(4) Ripples and noises: ≤1 %( RMS)
III The method for use
1. The method for use
(1) Power-on: check the input voltage whether it is normal voltage value or
not.
(2) Clockwise regulate the constant-current setting knob (6) to the maximum.
Place the power switch in “ON” position, the indicator light is on.
(3) Constant voltage setting: the knobs (6) should be clockwise regulated to
the maximum. Regulate the voltage regulation knobs (8) to set the necessary
voltage value, and then connect the load to the “+” and “-” output terminal. At
this moment the power supply is working under the condition of constant
voltage, the output voltage remains the same, while the output current changes

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with the load. When used in places with high demand, make sure one of the
output terminal “+” or “-” must reliably connects with post head “GND” so as
to reduce output ripple voltage.
(4)Constant current setting: Firstly, regulate the voltage to any value between
3-10V, and regulate the knob (6) to the minimum. (0A), and then use a lead to
make positive and negative polarities shorted. Regulate the Current regulation
setting knob (6) to the necessary current value. Remove the short lead, and
then regulate the voltage to the necessary value, connect the load, then you
can start your work. At this moment the power supply is under the constant
current. That is the current remains the same, while the voltage changes with
the load. (There will be slight sounds when positive and negative polarities are
shorted. That is normal phenomenon)
IV Matters need attention
1. Input voltage: Confirm the input voltage is AC220V±10% 50Hz or
110V±10% 60Hz.if the input voltage is wrong, the power supply can not work
normally, and even it will lead to serious result.
2. Working condition: For the purpose of heat dissipation, there should be
enough space around the power supply. The two sides and back of the power
supply should have more than 10cm space. This kind of power supply uses
intelligent fan controlled by temperature to cool. When inside temperature of

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the power supply is no less than 450C, the fan start to work, while the
temperature is less than 450C, the fan stop working.
3. The protective ground terminal of the tree-core power cord should be
reliably connected with the ground to ensure safety in use and reduce the
ripple.
4. Do not start the power supply with load, otherwise it easily damage the
power supply and load. When the load current is more than 10A, please
choose the back output terminal, tighten the output terminal to avoid
damaging the terminal which caused by large contact resistance. Please
regularly check the connecting terminal whether it is loose or not.
5. Over temperature protection: The power supply has over temperature
protection function. When inside temperature is higher than protection value,
the power supply will stop working. After the inside temperature is lower than
protection value, the power supply will come to work again. Do not use the
power supply in the condition that the temperature is higher than 400C. There
should be enough space for heat dissipation.
6. This serial is a kind of switch power supply. It has the function of about 2
seconds with time delay start-up (turn on the power supply, after about 2
seconds, the indicator light is on and the LED has display). Also it has the
function of about 1-5 seconds with time delay start-down.

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V Maintenance
1. If the fuse burned out, the power supply will stop working. Please replace it
with equivalent fuse. The crisper should not be opened unless something goes
wrong.
2. The power supply is precisely regulated before it goes out. Please do not
open the power supply unless you are a professional. If there is something
wrong, please contact with dealer. Do not repair the power supply by yourself
as there is high voltage circuit in the power supply.
VI attachment
User manual 1
Power cord 1