YIHUA 305D IV User manual

High-precision DC voltage
current regulator
Thank you for choosing this type of DC power supply. Please read the user guide
thoroughly before using, and keep it in a safe place for future reference.
Statement: The company reserves the right to improve and upgrade products,
product specifications and design are subject to change without notice.
305D
English
IV
INSTRUCTION MANUAL

When using an electrical appliance, basic precautions are required to always be
followed, including the following:
Read all instructions before using DANGER - To reduce the risk of electric shock:
1. This appliance can be used by children aged from 8 years and above and
persons with reduced physical, sensory or mental capabilities or lack of
experience and knowledge if they have been given supervision or instruction
concerning use of the appliance in a safe way and understand the hazards
involved.
2. Children are not allowed to play the machine.
3. Cleaning and maintenance shall not be made by children without supervision.
4. If the supply cord is damaged, it must be replaced by the manufacturer, its
service agent or similarly qualified persons in order to avoid a hazard.
5. Do not leave the appliance unattended when it is switched on.
6. High voltage in machine, amateurs do not dismantle machine.
7. People with defects in physical and mental or the one lack of using experience
is not supported to use the product unless under the professional person's
guide and instruction. Keep it far away from the children.
NOTED
1. AC input: service voltage must match the machine input voltage.(AC 110V/
220V)
2. There must be sufficient space around the power source for heat dissipation.
3. Output voltage overshoot limit: When switch on the power supply, output
voltage should be not exceed setting value.
4. Do not use the product in environments where temperatures exceed 40°C.
5. When charging the battery, do not reverse the positive and negative terminals
to avoid damage to the battery.
6. This product is of a fan-less design, full power output should be at least 4 hours.
For longer continuous operation, please set the usage control rate under 80%,
otherwise an artificial early failure may be possible. When ordering the product,
please reserve the balance according to the actual operating current.
WARNING
This DC stabilized switching power supply is designed for use in laboratories,
schools, production lines, and electronic repair. It has a small size and is
lightweight, which is very easy to transport and carry. It has high efficiency, high
load capacity, and low noise and is superior to linear power supplies.
I. Product Feature
Rated Working Condition and Machine Appearance
Input voltage
Frequency
Power
Working environment
Working environment humidity
Storage condition
Storage environment humidity
Machine dimension
Unit weight
AC 110V / AC 220V optional
50Hz/60Hz
194W
-10°C~40°C
<90%
-10°C~40°C
<80%
L282xW125xH156mm ±5mm
2.3kg ±50g
0-30V
≤0.01% +2mV
≤0.2% +2mV
Digital display of 1% ±1 characters
<0.3% Vrms
≤200PPM/°C
0-5A
≤0.1% +3mA
≤0.02% +mA
<1% Vrms
Digital display of 1% ±1 characters
II. Parameters
Regulation Voltage
Output voltage
Voltage stability
Load stability
Voltage display precision
Ripple noise
Temperature coefficient
Output current
Load stability
Current stability
Ripple noise
Current display precise
Regulation State
1 2

III. Panel Control Description
O.V.P
C.L.P
ON W
A
V
CC
CV
1
2
3
4
5
6
7
89
10
11
12
13
14
1. Model
2. Output voltage
3. Output current
4. Output power
5. Current coarse adjusting knob
6. Current fine adjusting knob
7. The output negative terminal
8. Connection wire
9. The output positive terminal
10. Power switch
11.Voltage coarse adjusting knob
12. Voltage fine adjusting knob
13. Constant current indicator
14.Constant voltage indicator
1. Connecting to the power source, set the machine input voltage to the same
with use voltage (AC110V/220V).
2. Turn on the power switch, indicator C.V light (current coarse and fine
adjustment knob does not 0 ), current and voltage display shows the “000” , a
voltage display the output voltage.
3. Adjust the voltage coarse/fine knob to the request voltage ( current coarse and
fine adjustment knob not 0), output voltage range: 0-30V DC.
4. When connecting to an external load to the “+”, “-” output terminals, output “+”
or “-” posts must have a reliable connection with GND terminal, it can reduce
the output ripple of power.
IV. Usage Instruction
Operation
1. Firstly, adjust voltage coarse and fine knob to the voltage value between 2 to 5V
(current coarse and fine adjustment knob is not 0).
2. And then adjust current coarse and fine knob to 0 (Anti-clockwise to the end).
3. Connect output terminal “+” and “-” with wire.
4. Then adjust the current coarse and fine knob to set the working voltage and
then you can continue your operation.
Current Setting
This machine is the type that the voltage and current can convert automatically. It
means that the regulator voltage and current keeps converting according to the
load change. The switching point between the regulation and the steady current
state becomes the transition point.
For example: When the machine is in stable state, if the output voltage is
constant, the output current will change according to the load and there is no any
change for output voltage. When the load increase(resistance decrease) , voltage
is down. The conversion of regulator voltage and current is shown from panel LED
indicator, CV indicator for regulator voltage and CC indicator for regulator current.
Voltage/Current Characteristics
3 4

Product certification
Maintenance records
Thank you for choosing this type of products, please read the following terms
before using:
1. From purchasing date within 7 days, under normal use(Non-artificial damage),
new package, not be disassemble and repaired ,enjoy replacement service.
2. From purchasing date within one year, under normal use, if there are quality
problem, not be disassemble and repaired ,enjoy free repair service.
3. For more than warranty, we provide a lifetime warranty service, free of labor
costs, charge only spare parts costs.
4. Failure to present warranty card during warranty period, the company will not be
a free service.
5. Users need warranty service, please contact your original sales unit.
6. When users need warranty service, please provide warranty card and purchase
invoice, or receipt of the certificate of the company seal.
7. Warranty does not include transportation costs and provide on-site service.
Warranty Card
Date of manufacture
Sales Date
Model NO.
Product ID
Examine QC
PASS
Upon examination products meet technical
standards
NO. Date for repair Cause Fix date Repairer