Matsusada Precision R4GT Series User manual

Instruction manual
F-RA-001-2R3
MODEL R4GT series
B/N: 217.9.166 *217.9.166* Rev. 0.12

Trademarks
◆Company names and product names in this document are the trademarks or registered
trademarks of their respective companies.
Note
◆All rights reserved.
◆
No part of this publication may be reproduced, stored in a retrieval system, or transmitted,
in any form, or by any means, mechanical, electronic, photocopying, recording, or
otherwise, without the prior written permission of Matsusada Precision.
◆
No patent liability is assumed with respect to the use of the information contained herein.
Moreover, because Matsusada Precision is constantly striving to improve its high-quality
products, the information contained in this manual is subject to change without notice.
Every precaution has been taken in the preparation of this manual. Nevertheless,
Matsusada Precision assumes no responsibility for errors or omissions.
Neither is any liability assumed for damages resulting from the use of the information
contained in this publication.
Warranty
◆For details, refer to the following website.
https://www.matsusada.com/support/manufacturer_warranty.html

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R4GT series
For Safe Use of the Product
◆Introduction
The product generates high-voltage and high-energy.
Therefore, wrongly handling or operating the product may result in death or serious injury and maybe
property damage as well. In order to use the product safely, read the instruction manual thoroughly before
use to understand how to use and operate it properly.
Please note that we will not be held responsible for any damage or loss caused by not following the warnings,
cautions, and procedures described in the manual.
Keep the manual with you so that you can read it whenever you want.
◆Symbols
Symbols are used in the manual and product, which indicate precautions to be observed for safe use.
Understand these symbols first and then read the manual thoroughly.
Some symbols below are not used in products.
Indicates a potentially hazardous situation, which, if not avoided,
may result in serious injury or death.
Indicates a potentially hazardous situation, which, if not avoided, may
result in minor or moderate injury or in property damage.
Indicates danger/warning/caution. Refer to
the instruction manual when this symbol
appears on the unit.
Frame or chassis terminal
Indicates the possible danger of electric
shock under specific conditions, which may
result in serious injury or death.
Ground terminal
High Temperature Caution:
Indicates the possible danger of injury by
high temperature under specific conditions.
Power ON
Indicates general prohibitions, including
warnings.
Power OFF
Indicates what must be followed.
Standby: Voltage is being
applied to the inside of the
product.
Protective earth terminal (ground terminal
for preventing electric shock)
Bistable push button switch
ON
Indicates the possible danger of death if you
drink it and burns or blindness if it attaches.
Bistable push button switch
OFF
Indicates the possible danger of exposure to
radiation.
Alternative Current

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R4GT series
◆Understand the risks.
The Product generates high-voltage and high-energy.
The product is designed for electrical engineers or the equivalents who install, wire, and operate it.
Read the instruction manual thoroughly before use and familiarize yourself with the proper use and danger
of the product.
◆Make sure to allow only specific people to handle the product.
Make sure to allow only the following people to handle the product:
1. who are electrical engineers or the equivalents and have already familiarized themselves with the
proper use and danger of the product, or
2. who are electrical engineers or the equivalents and have already been trained by the above-mentioned
people, or
3. who work under the supervision of the above-mentioned people.
If people other than those listed above install, wire, or operate the product, it may cause electric shock,
burnout, or injury.
◆Do not open or remove the case or panel of the product.
Do not disassemble, repair, or modify the product by yourself. High-voltage is applied to the inside of it.
Otherwise, it may cause electric shock, fire, or malfunction.
Moreover, if you do it, the safety and functions are not covered with the warranty.
◆The product does not suit to install and use in places where children may be present.
The product is designed to be installed in places such as factories or laboratories. Do not install and use it
where children may be present.
◆Make sure to ground it.
When the product has a protection ground terminal or GND terminal, make sure to ground it.
When the AC line input of it is an inlet type, connect the attached power cable or a power cable suitable
for your area to an outlet with the ground. Otherwise, it may result in electric shock or fire.
◆Regarding power cable
When a power cable is enclosed or attached to the product, do not use it for other products.
When no power cable is enclosed with the product, prepare the power cable suitable for the usage
environment and area by yourself.
◆Regarding the connection of power cable
Electrical engineers or the equivalents who have already been familiarized with the proper use and danger
of the product should connect the power cable to the AC input by referring to the instruction manual.
Regarding products that have acquired the safety standard, check the page describing the over-voltage
categories too.
◆Do not process or damage power cables
It may result in electric shock or fire.
◆Regarding the input voltage
Check the page describing the input terminals and input voltage in the instruction manual.
Do not provide any voltage out of the specifications.

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R4GT series
◆Regarding the fuse
The product builds in a protective fuse. In the case where a fuse holder is arranged outside of the product,
you can replace it by yourself. Refer to the instruction manual to replace it.
In the case where a fuse holder is not arranged outside of the product, you cannot replace it by yourself.
In this case, do not open the case or panel of the product and contact us.
◆The product is designed for indoor use.
Use the product indoors only, not outdoors. Even indoors, do not use it if there is a possibility of water
leakage, flooding, or snow covering.
◆Regarding operating temperature and humidity
Use the product within the range of the specifications describing in the instruction manual.
Do not use it in a place where the ambient temperature exceeds the specified range or a closed place.
◆Do not install the product in places where condensation may occur.
Otherwise, insulation deteriorates and it may cause electric shock, fire, or malfunction.
◆Do not place anything on top of the product.
Otherwise, they may fall or tumble from it.
◆Do not put anything into the product.
Do not put foreign objects such as metal or liquid into the product through the air inlets, air outlets, or other
openings. Otherwise, it may result in electric shock, fire, or malfunction.
◆Operate the product with the right hand.
Use only your right hand to operate the product and keep your left hand away from it, which can reduce
the risk of electric current flowing through the left hand to the vital organs of the body in the event of an
electric shock.
◆Do not touch the wiring/load connected to the output and any terminals/connectors during the
operation or just after turning output off.
Very high-voltage is on the terminals and connectors during the operation and even just after the output is
turned off. Touching them may result in serious injury or death by electric shock.
The terminals here mean all terminals like input and output terminals and terminals for communications
and remote controls.
◆Turn off the product before touching the wiring/load connected to the product and any
terminals/connectors on the product and cut it off from the AC input.
Before touching the terminals/connectors and wiring/load, turn off the product and unplug the AC input
cable from the outlet or turn off the AC input breaker. Then, check there is no voltage remained using a
tester.
Since the output and sense terminals are connected to condensers in it, there is high-voltage remained on
them even just after it is turned off.
In order to avoid electric shock, ground the terminals to discharge using a short-circuit grounding apparatus
and check the voltage again.
The terminals here mean all terminals like input and output terminals and terminals for communications
and remote controls.

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R4GT series
◆Level the product out to use for good heat dissipation.
Do not install the product upside down or sideways. If not, the inner heat dissipation will be insufficient.
It may result in smoke or fire due to components deterioration.
◆Do not install the product in a place where cold air directly blows to it.
It may result in electric leakage or burnout due to condensation.
◆Do not install the product in a place where it is exposed to corrosive gases or liquids.
It may result in smoke or burnout due to components deterioration.
◆Do not store or use the product in a place where conductive dust, such as iron power, can enter
through the air inlet/outlet.
Doing so may cause a short circuit, resulting in electric leakage, burnout, fire, or malfunction.
◆Do not install the product in a dusty place.
Accumulating dust in the air inlet will make hard to cool it down it, it may result in malfunction.
In that case, remove dust immediately.
◆Do not block the air inlet and outlet.
Secure 30 cm space at least around the openings.
If they are blocked, the product cannot show the rated performance due to the internal temperature
increase. Moreover, components deteriorate and it may result in smoke or fire.
◆Remove wiring to and from the product when work like welding near it is done.
◆Do not wipe the equipment with a dust cloth wet with chemicals (thinner or the like) or water.
Otherwise, it may result in an electric shock, electric leakage, or burnout due to water getting inside.
◆Regarding fan replacement
When products equip a fan, it has a lifetime. It will be worn out and deteriorated with the time passed and
its operation may become unstable. Also, its lifetime greatly varies depending on the usage environment
such as temperature, humidity, dust. It requires to be replaced at regular intervals to extend the lifetime.
For the replacement, contact us.
(It requires a replacement charge separately. Do not replace it by yourself, as there is a risk of electric
shock.)

Table of Contents
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R4GT series
Table of Contents
Page
For Safe Use of the Product ............................................................................................................................... i
Table of Contents ............................................................................................................................................... v
1Introduction············································································································································································································1
1-1 Introduction··································································································································································································1
1-2 Overview·······································································································································································································1
1-3 Features········································································································································································································1
1-4 Lineup·············································································································································································································1
1-5 Specifications·····························································································································································································2
2Before Use·············································································································································································································3
2-1 Unpacking····································································································································································································3
2-2 Initial Inspection························································································································································································3
2-3 Precautions for Handling······································································································································································3
2-4 Installation····································································································································································································4
2-4-1 Installation Conditions··································································································································································4
2-5 External View······························································································································································································5
2-5-1 Front Panel························································································································································································5
2-5-2 Rear Panel·························································································································································································5
2-5-3 External Dimensions·····································································································································································6
2-6 Remote Interface Connector (TB1) and Function Setting Switch (SW1)····································································7
2-6-1 Remote Interface Connector (TB1)·······································································································································7
2-6-2 Function Setting Switch (SW1)················································································································································8
3Basic Operation to Output·············································································································································································9
4Normal Operation···························································································································································································· 10
4-1 Operating Mode Description···························································································································································· 10
4-1-1 Constant Voltage (CV) Mode················································································································································ 10
4-1-2 Constant Current (CC) Mode················································································································································ 10
4-1-3 Crossover Mode··········································································································································································· 10
4-2 Output ON/OFF······················································································································································································ 11
4-3 Presetting the Output Voltage and Output Current·············································································································· 11
4-4 OVP (Overvoltage Protection) and OCP (Overcurrent Protection)············································································· 11
4-5 FINE switch······························································································································································································ 13
4-6 LOCK··········································································································································································································· 14
4-7 Power Failure Protection··································································································································································· 15
4-8 Last Setting Memory············································································································································································ 15
4-9 -LS (Remote Switch) ON/OFF························································································································································ 16
4-10 -LD (Interlock)······················································································································································································· 18
4-11 Remote Sensing·················································································································································································· 19
4-12 Error List·································································································································································································· 19
5Basic Operation······························································································································································································· 20
5-1 Single Operation···················································································································································································· 20
5-2 Series Operation···················································································································································································· 20
5-3 Parallel Operation················································································································································································· 21

Table of Contents
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Page
6Useful Features································································································································································································ 22
6-1 Master/Slave Setting (with the -LGmb Option)······················································································································ 22
6-1-1 Description of Master/Slave Function······························································································································· 22
6-1-2 Master/Slave Connection························································································································································ 23
6-2 Multi-set Function·················································································································································································· 24
6-3 Startup Menu··························································································································································································· 26
6-3-1 Setting the Startup Menu························································································································································· 26
6-4 Each Menu Mode·················································································································································································· 28
6-5 Startup Menu List·················································································································································································· 32
6-6 Delay Trigger Function······································································································································································· 33
6-6-1 Using the Delay Trigger Function········································································································································ 33
6-6-2 Stopping the Delay Trigger in an Emergency··············································································································· 33
6-6-3 Using the Delay Trigger Function in Master/Slave Configuration (with -LGmb Option)························· 33
7Analog Control·································································································································································································· 36
7-1 Local Programming Mode Operation·········································································································································· 36
7-2 Switching Local/Remote Mode (Voltage/Current Mode Setting)·················································································· 36
7-3 Remote Programming········································································································································································· 37
7-3-1 Voltage Program Setting with External Voltage··········································································································· 38
7-3-2 Voltage Program Setting with External Resistance··································································································· 38
7-3-3 Current Program Setting with External Voltage··········································································································· 39
7-3-4 Current Program Setting with External Resistance··································································································· 39
7-4 Monitor and Status Outputs····························································································································································· 40
7-4-1 Monitor Output·············································································································································································· 40
7-4-2 Status Output················································································································································································· 40
7-5 Parallel Operation················································································································································································· 42
7-6 Introduction of Pressure Welding Connector Tools············································································································· 44
8Troubleshooting······························································································································································································· 45

1 Introduction
1 R4GT series
1 Introduction
1-1 Introduction
Thank you very much for purchasing ourR4GT series, the ultra-low noise programmable DC power
supply.
We have taken all possible measures to ensure the quality control of our products.
Please follow the instructions in this manual to ensure full performance and safe use of the product.
We have applied our best to prepare this instruction manual, but if you find any unclear points, errors,
or missing contents, please contact us.
1-2 Overview
The R4GT series is a DC power supply for precision plating, based on the ultra-low noise DC power
supply R4G, which is equipped with a 4-digit meter and high-resolution D/A and A/D converters, and
enables more minute current setting and output.
It is also suitable for testing light-emitting devices, LEDs, and organic EL (OEL) that handle minute
currents.
Since it supports digital communication, it can be used in a wide range of applications from experiments to
automated lines.
1-3 Features
Voltage and current display with 4-digit indicators
It enables you to fine-tune its output more than ever before in units of "1mV to 10mV," and "0.01mA
to 1mA*".
* Model-dependent
High-speed response
High-speed response improves plating quality.
Various functions equipped as standard
Analog remote control and various digital interfaces are supported, making it easy to integrate into
automated lines.
Pulse/ramp sequence function (optional)
Pulse/ramp waveform can be set only with the unit, without using an external sequencer or PC.
1-4 Lineup
Model
Output
Voltage
[V]
Output
Current
[A]
Output
power
[W]
Minimum setting unit
Power
consumption
[VA]
Weight
[Kg]
Output voltage
[mV]
Output current
[mA]
R4GT6-0.3
0 to 6
0 to 0.3
1.8
1
0.1
Approx. 22
Approx. 3
R4GT10-0.01
0 to 10
0 to 0.01
0.1
10
0.01
Approx. 20
R4GT18-0.1
0 to 18
0 to 0.1
1.8
0.1
Approx. 22
R4GT18-0.2
0 to 0.2
3.6
0.1
Approx. 27
R4GT36-0.1
0 to 36
0 to 0.1
3.6
0.1
Approx. 30
R4GT36-0.2
0 to 0.2
7.2
0.1
Approx. 35

1 Introduction
2 R4GT series
1-5 Specifications
Item
Description
Input voltage
120Vac±10%, 50/60Hz, single phase
Output control
Local: Rotary encoder on the front panel
Remote: External control voltage, 0 to 10Vdc
Stability
0.05% of max. output voltage/8H
Temp. coefficient
0.01%/°C (Typ.) of max. output voltage, 0.02%/°C (Typ.) of max. output current
Output display
Output voltage: 4-digit digital indicator, accuracy ±0.3% rdg. + 2-dgt.
Output current: 4-digit digital indicator, accuracy ±0.5% rdg. + 4-dgt.
Protection circuit
Overvoltage protection (OVP), Overcurrent protection (OCP),
Power failure protection (PFP)
Other functions
ON/OFF by Remote switch, Key lock to prevent accidental operation, Last setting
memory, Remote sensing, Status signal output, Delay trigger function, Multi-set
function
Transient response
time
Recovery time: 50μs (at 10%⇔100% load regulation)
Operating
temperature
0℃to +40℃
Storage
temperature
-20℃to +70℃
Storage humidity
20% to 80% (no condensation)
Withstand voltage
Between input and output terminals, and between input terminals and chassis:
AC1000V/1 min.
Voltage to ground
±250V-DC *1(“+”or “-“terminal grounding possible.)
*1 When the -LH option is installed, it is ±500V-DC.
Operating characteristics
Model
Constant voltage characteristics
Constant current characteristics
Ripple
[mVrms]
Input
regulation
[mV] *1
Load
regulation
[mV] *2
Ripple
[mVrms]
Input
regulation
[mV] *1
Load
regulation
[mV] *2
R4GT6-0.3
0.5
1
2
1
1
5
R4GT10-0.01
0.5
2
R4GT18-0.1
3
R4GT18-0.2
5
R4GT36-0.1
2
3
R4GT36-0.2
5
*1 For AC±10% regulation
*2 For load regulation from 10 to 100%

2 Before Use
3 R4GT series
2 Before Use
2-1 Unpacking
After unpacking the box, check that the following accessories are supplied with the product. If the
accessories are different, missing, or broken, please contact us immediately.
<Accessories>
□
Instruction manual
1 ㍶
□
AC input code, three-core, single-phase
1 pc
□
MIL 26-pin male connector
1 pc
□
MIL 26-pin semi-cover
1 pc
□
CO-M cable, 2m long
1 pc
When the -LGmb option is installed.
□
CO-OPT cable
1 pc
When the -LGob option is installed.
2-2 Initial Inspection
After unpacking and before wiring input and output, check the product for any abnormalities.
Check the front panel, rear panel, and chassis for scratches, dents, or other signs of shock from
transportation or handling.
If you find any abnormalities, please contact the carrier and us.
2-3 Precautions for Handling
For the input voltage, check this instruction manual and the indication on the rear panel of the unit
itself.
Do not provide any voltage out of the specifications. Doing so may result in fire or malfunction.
Do not open or remove the case cover of the unit. Doing so may result in electric shock or
malfunction.
When changing the system, do it after turning off the power of all devices that
make up the system.
Generally, connect one of the output terminals, +/-, to the GND terminal with a short bar.
Firmly Insert the AC input cord plug into an outlet.
The heat sink may become hot. Do not touch as it may cause burns.

2 Before Use
4 R4GT series
2-4 Installation
2-4-1 Installation Conditions
Set the product on a level place to use.
The top, both sides, and bottom of the unit are air inlet/outlet for cooling air.
Secure a space at least 10 cm or more around the unit for good ventilation.
The unit is a self-cooling type. If the unit is installed in a rack, equipment, or
enclosed cabinet, take measures such as forced ventilation to prevent exhaust
heat from returning to the air inlet.
If dust collects in the air inlet, remove it immediately.
it prevents the unit from cooling.
Do not place anything on top of the product. It prevents the unit from cooling.
Do not expose the unit to dusty, corrosive, or inflammable gas areas.
Do not install the product in a place where condensation may occur.
Do not use substitute parts or modify the internal circuits of the product.
For repair or modification, please contact us.
Prevent liquids or metals from entering the product through the air inlet and outlet.
It may result in malfunction, electric shock, or fire.
Do not store or use the product in a place where conductive dust, such as iron
powder, can enter through the air inlet/outlet. Doing so may cause a short circuit,
resulting in electric leakage, burnout, fire, or malfunction.
When doing some work near this product such as welding, disconnect all
connection wires (input/output wiring, signal wires, etc.) from the product before
working on it.
Ensure safety in case of malfunction.
In the event of a malfunction, unplug the AC input cord from the power outlet.

2 Before Use
5 R4GT series
2-5 External View
2-5-1 Front Panel
(1) Voltmeter
(2) Ammeter
(3) Remote enabled indicator (REMOTE
LED)
(4) OUTPUT ON indicator (OUTPUT LED)
(5) OUTPUT ON/OFF switch
(6) + Output terminal
(7) - Output terminal
(8) GND terminal
(9) Model name
(10) Voltage mode indicator (CV LED)
(11) Current mode indicator (CC LED)
(12) Output voltage setting dial
(13) FINE switch
(14) Output current setting dial
(15) SET switch (SET LED)
(16) OVP/OCP switch (OVP/OCP LED)
(17) LOCK switch (LOCK LED)
(18) POWER ON/OFF switch
(18)
(7)
(6)
(8)
(12)
(14)
(10)
(11)
(17)
(3)
(1)
(16)
(5)
(2)
(4)
(9)
９
(13)
(15)
FINE
REGULATED DC POWER SUPPLY
POWER
LOCK
OCP
SET
OVP/
CV
CC
V
mA
OUTPUT
VOLTAGE
CURRENT
R4GT18-0.2
－
＋
GND
!
|
○
REMOTE
2-5-2 Rear Panel
INPUTAC**V
(1)
The "**" in "INPUT AC**V" varies depending
on the type of input voltage.
(1) AC input connector
(2) Master/Slave input/output terminals,
TB2
(3) Function setting switch, SW1
(4) One control ON/OFF switch
(5) Remote sensing ON/OFF switch
(6) Remote interface connector, TB1
(5)
(4)
(3)
(2)
(6)

2 Before Use
6 R4GT series
2-5-3 External Dimensions
Unit: mm

2 Before Use
7 R4GT series
2-6 Remote Interface Connector (TB1) and Function Setting Switch (SW1)
2-6-1 Remote Interface Connector (TB1)
This product is a power supply unit that generates a large current.
If a large current flowed into TB1 due to an incorrect connection, there might be a risk of
failure or burnout.
Be sure to confirm the following precautions before use.
Do not connect anything to PIN 4, 8, 9, 14, 18, 20, 22, 23, 24, and 25.
Doing so may lead to unit damage.
Do not directly connect PIN 5 and PIN 10 to the +S.
Do not directly ground PIN 5 and PIN 10 to the ground.
When grounding, connect the + output terminal to the ground.
Do not wire near sources of large noise. Doing so may result in malfunction or
breakdown.
(Note) If the above situation is unavoidable, it is recommended to use the -LGob
option (Optical GPIB/RS-232C interface board).
PIN 5 and PIN 10 are internally connected to +S. Therefore, equipment connected
to TB1 should be floating.
The wiring from the following pins should be short (a few meters or less).
TB1 PIN 1, 2, 3, 5, 7, 10, 15, 16, 17, 21, and 26
Whenusingthisunitwiththe "-"outputterminalgrounded,avoltageequaltotheoutput
will be applied to TB1 pins. Be careful because this may be dangerous.
However, PIN 6, 11, 12, 13, 19, and 26 are insulated from other PINs.
For details, refer to [7-4-2 Status Output].
Do not connect PIN 5 or PIN 10 on the
TB1 to the "+" output.
Do not share the common for the external
voltage inputof each unitwhen connecting
the units in series.
Load
10
5
TB1
Load
1
2
5
10
1
2
5
10
1
2
25
26
PIN 2: Current mode program input
PIN 4NC
PIN 6Common for external status output (CV, CC, FLT, OUTPUT, POWER ON)
PIN 8NC
PIN 10 + Common (LS, LD)
PIN 12 Current mode status output
PIN 14 NC
PIN 16 + Sense
PIN 18 NC
PIN 20 NC
PIN 22 NC
PIN 24 NC
PIN 26 POWER ON status output
Voltage mode program input PIN 1
Output current monitor output
PIN 3
+ Common PIN 5
LD door switch input
PIN 7
NC
PIN 9
FLT status output PIN11
Status output for voltage mode PIN13
Output voltage monitor output
PIN15
- Sense
PIN17
OUTPUT status output
PIN19
Remote switch input: PIN21
NC PIN23
NC PIN25

2 Before Use
8 R4GT series
2-6-2 Function Setting Switch (SW1)
SW1-1
Do not use
SW1-2
Do not use
SW1-3
Do not use
SW1-4
Do not use
SW1-5
Current program switching
(OFF: External voltage, ON: External resistance)
SW1-6
Current local/remote mode switching (OFF: Remote, ON: Local)
SW1-7
Voltage program switching
(OFF: External voltage, ON: External resistance)
SW1-8
Voltage local/remote mode switching (OFF: Remote, ON: Local)
ON
SW1
8
7
6
5
4
3
2
1

3 Basic Operation to Output
9 R4GT series
LOCK
OCP
SET
OVP/
CV
CC
V
mA
OUTPUT
REMOTE
LOCK
OCP
SET
OVP/
CV
CC
V
mA
OUTPUT
REMOTE
LOCK
OCP
SET
OVP/
CV
CC
V
mA
OUTPUT
REMOTE
FINE
REGULATED DC POWER SUPPLY
POWER
LOCK
OCP
SET
OVP/
CV
CC
V
mA
OUTPUT
VOLTAGE
CURRENT
R4GT18-0.2
－
＋
GND
!
|
○
REMOTE
3 Basic Operation to Output
The following describes the basic operation from turning on the unit to outputting from the unit.
Connect the load to the unit.
Set the protection values for the overvoltage and overcurrent to the maximum. (R4GT18-0.2)
Set voltage/current values to output.
Press the [OUTPUT ON/OFF] switch.
Starting output
Setting voltage/current values
Starting output
Setting OVP/OCP
* Make sure that the output
has already been turned
off with the [OUTPUT
ON/OFF] switch.
(OUTPUT LED: OFF)
Otherwise, the connected
load may be damaged.
Load
OVP/OCP LED: ON
Press OVP/OCP
SET LED: ON
Press SET
VOLTAGE
CURRENT
Output voltage setting
(Voltage setting dial)
Output current setting
(Current setting dial)
VOLTAGE
CURRENT
OVP setting
(Voltage setting dial)
OCP setting
(Current setting dial)
Connecting the Load
Press OUTPUT
OUTPUT LED: ON

4 Normal Operation
10 R4GT series
4 Normal Operation
4-1 Operating Mode Description
R4GT series power supply unit has two operation modes (constant voltage mode and constant current
mode).
Here describes each mode.
The operation mode is determined with the following parameters.
Output voltage setting value ：Vset
Output current set value ：Iset
Load resistance ：RL
4-1-1 Constant Voltage (CV) Mode
When the load current ILis lower than the setting value Iset (IL<Iset;IL=Vset/RL), the unit operates in
CV mode.
InCV mode,the voltagewillbe constantat the setvalue (Vset) andthe loadcurrentILvariesdepending
on the load.
When using the unit in CV mode, set a current value larger than the required current value with the
current setting dial.
A required voltage can be set unless it does not exceed the set current value.
4-1-2 Constant Current (CC) Mode
When the load current ILis greater than the setting value Iset (IL>Iset ), the unit operates in CC mode.
In CC mode, the current will be constant at the set value (Iset) and the load voltage varies depending
on the load.
RL ＝ Load resistance
Vset ＝ Output voltage set value
Iset ＝Output current set value
4-1-3 Crossover Mode
In response to changes in load response, the crossover system automatically switches the unit
operating mode.
For example, in CV mode, if the load fluctuates and the current exceeds the current set value, it
automatically switches from CV mode to CC mode. In CC mode, when the load fluctuates and the
load voltage exceeds the set value, it automatically switches from CC mode to CV mode.
Output Voltage
Vset
Constant voltage region RL ＞
RL
＝
RL ＜
Iset
Output Current
Crossover point
Constant current region
Vset
Iset
0
Vset
Iset
Vset
Iset

4 Normal Operation
11 R4GT series
LOCK
OCP
SET
OVP/
CV
CC
V
mA
OUTPUT
REMOTE
LOCK
OCP
SET
OVP/
CV
CC
V
mA
OUTPUT
REMOTE
4-2 Output ON/OFF
Press the [OUTPUT ON/OFF] switch to turn on and off the output.
When the OUTPUT LED is lit, the set voltage and current are output from the output terminals.
When the OUTPUT LEDis unlit the output turns off,which means there is no voltage applied to the output
terminals.
4-3 Presetting the Output Voltage and Output Current
Pressing the [SET] switch on the front panel displays the set voltage value on the voltmeter and
the set current value on the ammeter for approx. two seconds.
Set the output voltage and output current by pressing the [SET] switch and rotating the output
voltage and current setting dials.
When the [OUTPUT ON/OFF] switch is "ON" (OUTPUT LED is lit), note that both voltage and current
have been output, so be careful to avoid electric shock.
When the [OUTPUT ON/OFF] switch is OFF (OUTPUT LED is unlit), turning the voltage/current
dial will display the set voltage value on the voltmeter and the set current value on the ammeter
for approx. two seconds, just as the same as when the [SET] switch is pressed.
4-4 OVP (Overvoltage Protection) and OCP (Overcurrent Protection)
OVP and OCP protect loads from programming errors, improper voltage and current settings, and power
supply unit malfunctions.
Setting Procedures:
1. Turn off the [OUTPUT ON/OFF] switch.
2. Press the [OVP/OCP] switch.
For approx. two seconds, the OVP set value is displayed on the voltmeter and the OCP set
value is displayed on the ammeter.
3. Turn the voltage setting dial to set the desired OVP value and the current setting dial to set the
desired OCP value respectively.
4. Turn the [OUTPUT ON/OFF] switch ON again and slowly increase the output voltage and
current to check that the output turns OFF at the OVP/OCP set voltage and current values.
The OVP/OCP function can be disabled by setting the value to "0".
* When the protection is disabled by setting the value to "0", use the unit with great care for the output.
SET LED: ON
Voltage and current setting values are indicated for approx.
two seconds.
Press SET
VOLTAGE
CURRENT
Output voltage setting
(Voltage setting dial)
Output current setting
(Current setting dial)
Press OUTPUT
The output is turned on
when the OUTPUT LED
is lit.

4 Normal Operation
12 R4GT series
LOCK
OCP
SET
OVP/
CV
CC
V
mA
OUTPUT
REMOTE
About OVP:
When the output voltage becomes larger than the set OVP value, OVP is activated and the output is
turned off.
When OVP is activated, the screen displays “OVP/Err1”, the output is turned off, and the OUTPUT
LED goes off.
To clear the state, press the [OUTPUT ON/OFF] switch.
(The screen will shift from "OVP/Err1” to the normal one.)
To restart the output, adjust the output voltage or OVP value, then set the [OUTPUT ON/OFF]
switch to "ON". The OUTPUT LED will be lit when the output turns ON.
About OCP:
When the output current becomes larger than the set OCP value, OCP is activated and the output is
turned off.
When OCP is activated, the screen displays "OCP/Err5", the output is turned off, and the OUTPUT
LED goes off.
To clear the state, press the [OUTPUT ON/OFF] switch.
(The screen will shift from "OCP/Err5” to the normal one.)
To restart the output, adjust the output current or OCP value, then set the [OUTPUT ON/OFF] switch
to "ON". The OUTPUT LED will be lit when the output turns ON.
The OVP/OCP LED will be lit
and display OVP/OCP set
values for approx. two seconds.
Press OVP/OCP
VOLTAGE
CURRENT
OVP setting
(Voltage setting dial)
OCP setting
(Current setting dial)
If the output voltagebecomes larger than the OVP set
value or the output current larger than the OCP set
value, the output is turned off.