Kenwood pds20-18 User manual

REGULATED DC POWER SUPPLY
PDS20-18/PDS36-10
PDS60-6
SERVICE MANUAL
KENWOOD TMI CORPORATION
© 1998-4/B51-1132-00 (K/K)
POWER
REGULATED DC POWER SUPPLY PDS36-10
0 +36V (10A)
-+
PRESET KEYLOCK/LOCAL
MEMCRY
VOLTAGE
CURRENT
FAST/SLOW
CC
CV
CVP
OUTPUT
8.8.8.8.
8.8.8.8.
0 +60V (6A)
GND
Front Panel
(PDS20-18 ; A63-0309-03)
(PDS36-10 ; A63-0311-03)
(PDS60-6 ; A63-0315-03) Handle (K01-0556-05) Push Button (K29-7204-04)
Circuit Protector
(S79-0625-05) Terminal ; White (E21-0807-03) Terminal ; Red (E21-0806-03)
Rubber Foot
(J02-0506-05)
Terminal ; White
(E21-0807-03) Terminal ; Red
(E21-0806-03)
Terminal ; Black
(E21-0808-03)
Rotary Encoder
(K21-0911-04)
PDS-20-18(K)1,1(98.12.317:07 y[W 1

PDS20-18/PDS36-10/PDS60-6
2
The following instructions are for use by qualified personnel only. To avoid electric shock,
do not perform any servicing other than contained in the operating instructions unless you
are qualified to do so.
WARNING
CONTENTS
SPECIFICATIONS......................................................................................................... 3
CIRCUIT DESCRIPTION................................................................................................6
BLOCK DIAGRAM........................................................................................................11
ADJUSTMENT............................................................................................................. 18
PARTS LIST (UNIT)..................................................................................................... 21
PARTS LIST (ELECTRICAL)....................................................................................... 22
SCHEMATIC DIAGRAM .............................................................................................. 35
P.C. BOARD ................................................................................................................ 42
PDS-20-18(K)1,1(98.12.418:10 y[W 2

Model name PDS20-18 PDS36-10 PDS60-6
Rated output voltage (V) 20 36 60
Rated output current (A) 18 10 6
Output
Output voltage range (V) 0-20 0-36 0-60
Output current range (A) 0-18 0-10 0-6
Rated output power (W) 360
Constant voltage characteristics
Power regulation 0.005% +1 mV (for 10% source voltage fluctuation)
Load regulation 0.005% +2mV (for 0 to 100% fluctuation)
Ripple noise, p-p
(Measured with20MHz oscilloscope) 30 mVp-p
Ripple noise, rms (5 Hz – 1 MHz) 1mVrms 1 mVrms
Transient response (typ.) 100 µsec
Temperature coefficient (typ.) 100 ppm/°C
Rise time (typ.) Full load/no 100 msec/100msec
Fall time (typ.) Full load/no load 150msec/1000msec
Analog remote control setting accuracy
(IF 30AN optional board is used)
External voltage (+ curve) : 0 to 10V
External voltage (- curve) : 10 to 0V
External resistance (+curve): 0 to10kΩ3% 50mV
External resistance (- curve) :10k to 0Ω3% 100mV
Constant current characteristics
Power regulation 5mA 1mA
Load regulation 5mA
Ripple noise, rms (5 Hz – 1MHz) 10mArms 5mArms
Temperature coefficient (typ.) 100ppm/°C
Analog remote control setting accuracy
(IF 30A optional board is used)
External voltage (+ curve) : 0 to 10V
External voltage (- curve) : 10 to 0V
External resistance (+curve): 0 to10kΩ3% 50mA
External resistance (- curve):10k to 0Ω3% 100mA
Meter and display
Display & accuracy
(23 5°C) 4 digits, LED, 0.1% rdg 2 digits 3 digits, LED,
0.1% rdg 2 digits
Voltmeter Min. reading 10mV 100 mV
Display & accuracy
(23 5°C) 4 digits, LED, 0.5% rdg 2 digits 3 digits, LED,
0.5% rdg 2 digits
Ammeter Min. reading 10mA
In constant voltage operation CV LED is lit.
In constant current operation CC LED is lit.
Output ON indicator OUTPUT LED is lit.
PDS20-18/PDS36-10/PDS60-6
3
SPECIFICATIONS
PDS-20-18(K)1,1(98.12.317:07 y[W 3

PDS20-18/PDS36-10/PDS60-6
4
SPECIFICATIONS
Model name PDS20-36 PDS36-20 PDS60-12
Output signals
In constant voltage operation (option) Open collector, active Low
In constant current operation (option) Open collector, active Low
Alarm circuit operation Open collector, active Low
Output voltage monitor (option) 0 to 10V, F.S.accuracy: 3%
Output current monitor (option) 0 to 10 V, F.S.accuracy: 3%
Operation functions
OUTPUT key Turns output on and off. Set to OFF automatically when power
is turned on.(Possible to select automatic ON setting.)
VOLTAGE key Changes output voltage using rotary encoder.
CURRENT key Changes output current using rotary encoder.
OVP key Displays OVP circuit operating voltage on front panel,
which is variable between 10 and 110% of F.S.
KEY LOCK (LOCAL) key Locks keys and knobs (except POWER switch).
Also remove remote control.
PRESET 1 – 3 keys Used with MEM key to memorize three output voltage and
currents.
MEM key Used with PRESET keys to memorize
three output voltage and currents.
FAST/SLOW key Changes output voltage and current setting speed.
ON/OFF control Enabled with input contact signals.
POWER switch shut-down Enabled with input contact signals
Output voltage remote sensing Compensates for 1 V voltage drop on single side.
Protector circuit
Output over voltage (OVP) Variable between 10 and 110% of F.S.Turns off
Input POWER switch when OVP functions.
Output over current(OCP) Turns off input POWER switch at 115% or more of F.S.
Overheat (OHP) Turns off input POWER switch at internal heat sink
Temperature over preset value.
Soft OVP (OVD) Set from external controller in remote control mode.
Output is turned off when soft OVP is active.
Environmental conditions [Indoor use only]
Altitude Up to 2000m
Overvoltage category
Pollution degree 2
Operating temp. range 0 to 40°C
Operating humid. range 30 to 80%RH
Storage temp. range -20 to 70°C
Storage humid.range 20 to 80%RH
To-GND voltage 250 Vdc
Coolicg method Front air intake type forced air cooling
with fan motor insulation resistance
Insulation resistance
Chassis to power input 500Vdc, 30 MΩor more
Chassis to output terminal 500Vdc, 20 MΩor more
PDS-20-18(K)1,1(98.12.317:07 y[W 4

PDS20-18/PDS36-10/PDS60-6
5
SPECIFICATIONS
Model name PDS20-36 PDS36-20 PDS60-12
Dielectric strength
Chassis to power input 1.5 kVac, 1minute
Power input to output terminal 2.3 kVac 1 minute
Source voltage
Input voltage 100 to 240 Vac, 50/60 Hz single-phase
(this equipment is designed to operate
with 10% tolerance for rated voltage.)
Power factor (typ) 95%
560 W 520 W
Power consumption (typ) 600 VA 550 VA
Dimensions /Weight
Dimensions/Maximum dimensions(W)
210 /210 mm
(H) 124 /124 mm
(D) 405 / 465.5 mm
Weight 6.3kg
Accessories
Instruction manual 1
Power cord 1 (3-core cable, 2 meters)
Output terminal protector Cover : 1
GND cable 1
Egg-shape lug terminal 1
Options
Analog I/O board Controls output voltage and current using external voltage and resistance. Output monitored voltage and current and other
signals.
GP-IB board Sets and reads back voltage and current,
turns on and off output. Reads back status.
RS-232C board Sets and reads back voltage and current,
turns on and off output. Reads back status.
Output capacity extension
Collective parallel connection control Master-slave system, up to 3 units
Collective series connection control Master-slave system, up to 2 units
Regulatory information
LVD EN61010-1 & A2 (1995)
EMI EN55011 (1991) CLASS A
EMS IEC801-2 (1991) 8 kVAD IEC801-3 (1984) 3 V/m
IEC801-4 (1988)
Harmonic current Emission EN61000-3-2 (1995)
PDS-20-18(K)1,1(98.12.317:07 y[W 5

CONTROL UNIT(X77-2120)
Digital-to Analog Converter Circuit
Various signals received from the CPU unit are
isolated by PH1 to PH4. Various control signals
are output by IC4 to IC6. Data extracted by IC10
and IC11is input toIC12 (referenceDAC) and IC14
(monitor DAC), whichconvert the data into analog
signals.
Voltage and current monitor signals and CV/CC
status and otherstatus signals areinput to IC7 and
IC8 and is olated by PH5. The remote OUTPUT
ON/OFF signals fromthe rear panelare isolated by
PH6 andPH7 and returned to the CPU unit.
IC9 is the EEPROM for storing the calibration data,
data set on the panel, etc.
CV/CC Control Circuit
The voltage and current reference voltage output
by IC12 is about +2.8 V at the full scale, which is
amplifier to about 5 B by a reference amplifier
consisting of IC106.
In the CV operation mode, the voltage monitored
by means of + sensing is compared with this
reference voltage by R139, R137 and R225. The
error amplifier IC105-1/2 output the CV control
signal.
In theCC operationmode,the currentmonitorsignal
detected by the power unit is compared with
this
reference voltage by R140 and R141. The error
amplifier IC105-2/2 output the CC control signal.
In the slave operation mode, a signal input fromthe
masterunitis usedas thereferencesignalforcontrol.
The CV or CC control signal is selected by D113
and D114 and sent to the power unit drive circuit.
The operation voltage is about –3V.
Voltage, Current and “OVP Set
Voltage”
Monitor Circuit
The voltage detected by means of + sensing is
output as thevoltagemonitorsignal(about +2.8Vat
the full scale) by the monitor amplifier IC107-2/2.
The current monitor signal detected by the power
unit
is output as the current monitorsignal (about +2.8V
at the full scale) by the monitor amplifier IC107-1/2.
The OVP signal set on the panel is output as OVP
set voltage monitor signal (about +2.8 V at the
maximum voltage) through the buffer amplifier
IC103.
This monitor circuitis a sequential comparatorcircuit.
Output monitor signals are selected by IC15,
compared with the monitor reference signal from
IC14 (monitorDAC) by IC16, and then returned to
the CPU unit.The OVP set voltage monitor signal
can only be selected when the OVP key on the
panel is pressed.
Alarm Circuit
Several protector circuit are used : Variable
overvoltage (OVP), maximum overvoltage (MAX
OVP), pre overvoltage (PRE OVP), overcurrent
(OCP), overheat (OHP) and pre overheat (PRE
OHP). The pre overvoltage, overcurrent,
ovrtheat andpre overheatprotectorcircuitsoutput
alarm signals when they detect abnormalities.
Voltageofabout +2.8Visproducedby IC104 andis
divided by the semi-fixed variable resistor on the
panel to make the setreference voltage of theOVP
circuit.The voltage detected by a comparator circuit
consisting of IC101 by means of + sensing is
compared with the reference voltage.
An alarm is output if such comparison results in an
error.The MAX OVP circuit runsinthesameway on
the –3 V reference voltage determined by D108.
Output alarmsignals, except OHP, are latched by
IC108 and IC109. Atrip signal activates the main
switch control circuit to turn off the main switch.
Other Circuit
The circuit consisting of Q110 to Q112 output
signals for turning on oroff the bleedercircuit of the
power nit.
When the output is off and the output level has
lowered sufficiently, PH106 functions to turn off the
bleeder circuit. IC112 andIC113produce 5Vfor
the digital ICs and DACs from 15 V.
PDS20-18/PDS36-10/PDS60-6
6
CIRCUIT DESCRIPTION
PDS-20-18(K)1,1(98.12.317:07 y[W 6

PDS20-18/PDS36-10/PDS60-6
7
CIRCUIT DESCRIPTION
POWER UNIT(X68-1970)
Power Control Circuit
Q12 uses the control signals from the control unit
to control the current of the constant current
circuit consisting of Q13 and to drive Q11. Q11
supplies the base currentto Q1 to Q10.
The collector emitter voltage of Q1 to Q10 is
detected and supplied as the Vce voltage to the
secondary voltage detector circuitof theAC unit.
Current Detector Circuit
R46 detects theoutput current. IC 2/2 amplifier it
as shown inTable 1 and outputs amplifier current to
the control unit. The current is reversed by IC1
1/2 and used as the reference current forthe slave
side in the one control paralleloperationmode.
Model Gain
20-18 33 timeas high
36-10 33 timeas high
60-6 36 timeas high
Table 1
Bleeder Circuit
Two bleeder circuit are used : Input bleeder
circuit, and output bleeder circuit.
The input bleeder circuit has a constant current
circuit consisting ofQ17 andQ19. Itbleeds current
as shown in Table 2. When the voltage exceeds
value shown inTable 2,Q14 functions and reduces
the bleeder to about half. When the current
exceeds the output current shown in Table 2, the
comparatorIC3 1/2 function and turns on Q16 to
deactivate the bleeder circuit.
The output bleeder circuit has a constant current
circuit consisting of Q20. It bleeds current as
shown in Table 3. It is turned on or off by the
bleedersignal output by the control unit.
Model Input side
Bleeder current
Switching
Voltage Off
Current
20-18 About1A About20V About3.5 A
36-10 About1A About10V About 3 A
60-6 About0.5A About30V About 1.5 A
Table 2
Model Output side Bleeder current
20-18 About 150 mA
36-10 About 80 mA
60-6 About 50 mA
Table 3
Alarm Detector Circuit
This unit employs three alarmdetector circuits : Pre
overvoltage, overcurrent,and overheat detector
circuits.
The pre overvoltage detector circuit has a
comparator IC4 1/2, which compares the input
voltage. When theinputvoltage exceedsthe level
shown inTable 4,thecircuit outputs analarm signal.
The overcurrent detector circuit has a comparator
IC4 2/2, which outputs an alarmsignal when the
current detected by IC1 exceeds about 115% of the
full scale level. The IC4 2/2 also serves as an
erroramplifier and provides CC control when the
output current reaches about 115% of the full scale.
The overheat detector circuit has a TS1
thermal switch on the heat sink. This switch
functions and circuit outputs an alarmsignal when
the temperature exceeds about 110 .
Model Detection voltage
20-18 About 30V
36-10 About 50V
60-6 About 75V
Table 4
PDS-20-18(K)1,1(98.12.412:07 y[W 7

CPU UNIT(X77-2110)
CPU
IC7 (CPU) runs on 16 MHz clock pulses
generated by the X1 quartz oscillator.
Panel Switches (S1 toS10) and
Interruption Circuits (IC21 and IC22)
When any oftheswitches S1 toS10 onthepanelis
pressed, either input of the input port IC9 goes
“High”. At that time, IC21 and IC22 cause an
interruption to the CPU.
Rotary Encoder (S11)
Signals to the rotary encoder are processed
by IC12, IC23 to IC25 and IC28 first.
Processed and output data is latched by
IC11 and input to the input port
(pins 17 and 15) of IC14.
AsignalforclearingIC11is output by theCPU inthe
program loop.
Input Ports (IC9 and IC14)
Three types of data and signals shown
below are inputto the input ports, in addition
to signals from the panel switches and
encoder :
Serial data from the control unit
Signal issuedwhen the OUTPUTswitch is
turned on
S
1)
2)
3)
1)
2)
ignalissued when the OUTPUT switch is
set to the remote control position
These signals are read in the program loops and
sent to the CPU by IC9 and IC14.
Output Ports (IC10 toIC19)
IC16
The below-shown signals to the control unitare
output from the IC16 output port. These signals
are isolated by the control unit.
serial data to be sent to the D/Aconvertercircuit
Clock pulses for operating various elements in
the D/Aconverter circuit.
Strobe signalsforcontrollingtheD/Aconverter
circuit
IC17
Signals for the panel unit display driver
(IC1and IC2) are output by IC17.
IC18 and IC19
Signals for turning on theLEDs (D1 to D10) on the
panel unit are output by IC18 and IC19 (pins 18
and 19). Signals for controlling the flow of the RS-
232C interface are output by IC19 (pin 12).
IC10
Signals for controlling various optional boards are
output by IC10.
Others
Reset signal
IC27 outputs a signal for resetting the CPU
when thePOWER switch is turned on.
Driver
IC8 divides 8 MHz clock pulses output by the
CPU into 4 MHz pulses, which are output
from the IC10 port and used for optional
boards.
Panel unit X66-1600-00
IC1 and IC2 from a driver for the seven segment
LED indicator (ED1 to ED8). ED1 to ED8 are
controlled by signals output by IC17 (CPU
unit).
3)
PDS20-18/PDS36-10/PDS60-6
8
CIRCUIT DESCRIPTION
PDS-20-18(K)1,1(98.12.317:07 y[W 8

PDS20-18/PDS36-10/PDS60-6
9
CIRCUIT DESCRIPTION
MOTHER UNIT (X67-1420)
+15 V Rectifier and Smoother
Among electric power transmitted from the
primary side through the main transformer (T1),
this circuit producesrectified and smoothed+15 Vto
be supplied to IC1 in theAC unit.
Main Power Primary Side Rectifier
and Smoother
Diode D1 rectifiesAC power and capacitor C4
smoothes it.
Capacitor C4 stores voltage about 2 times as
high as theAC voltage.
Sub-Power Switching
Electric power having passed throughdiodeD1 and
stored in capacitor C4 passes through the sub-
transformer(T1) and is switched by Q1 by means
of ringingchoke conversion(RCC). Theoscillation
frequency is about 60 kHz when the input AC
voltage is 100 V or about 120 kHz when the input
AC voltage is 200 V. Q1 is controlled by signals
from thesub-power control (D).
Sub-Power Control
PH1 and IC2 output signals from the circuit (J) for
detecting the voltage of the internal +5 V power
(CPU unit). This sub-power control circuitcontrols
switching of Q1 based on such signals.
Internal -3.5 V Rectifier and Smoother
This circuit produces rectified and smoothed internal
voltage of 3.5 V at pins 15 and 16 of the sub-
Transformer (T1), which supplied to the power
Unit (X68-1970-0x) and control unit(X77-2120-0x).
Internal 15 V Rectifier and Smoother
This circuit produces rectified and smoothed
Internal voltage of 15 V at pins 10 to 12 of the
sub-transformer (T1), which is supplied to the
power
unit (X68-1970-0x) and control unit (X77-2120-0x).
Internal 15 V Rectifier and Smoother
This circuit produces rectified and smoothed
Internal voltage of 15 V at pins 7 to 9 of the
sub-Transformer (T1), which is supplied to the
AC unit (X68-1980-0x).
Internal +5 V Rectifier and Smoother
This circuit produces rectified and smoothed
Internal voltageof+5Vatpins 13and14of thesub-
Transformer (T1), which issupplied tothe CPU unit
(X77-2110-00).
Secondary Side Voltage Detector
This circuit detects voltage using R22 and R23 and
outputs controlsignals tothe sub-power control(D)
throughPH1 and IC2 in order tomake the internal
+5 V constant.
Main Switch Control
This circuit shuts down the main switch through
PH2 using theTrip+ signal from the control unit.
PDS-20-18(K)1,1(98.12.317:07 y[W 9

PDS20-18/PDS36-10/PDS60-6
10
CIRCUIT DESCRIPTION
AC UNIT (X68-1980)
Line Filter
This filter filtrates AC power and feeds filtrated
power to the primary side rectifier (B).
Main Power Primary Side Rectifier
Diode D4 in this rectifiercircuit rectifiesAC voltage
and supplies rectified power to the mainpower
switching circuit (D).
Primary Side Current Detector
T h e p r imar y s i de A C current is detected at this
transformer (T3) and fed to the control IC (IC1).
Main Power Switching
This main power switching circuit uses Q4 to Q 7
to switch AC voltagerectifiedby D4. Q4 toQ7 are
driven by Q2 and Q3 and controlled based on
signals output by IC1. The switching frequency is
about 135 kHz.
Main Power Control
The IC1-12(ON/OFF) terminal goesLow when the
main output power is off. It goes High when the
main output power is on. Signals for controlling Q2
and Q3 are output from the IC1-8 (OUT) terminal.
Triangular wave signals of the frequency decided
by R5 and C8 (about 135 kHz) are output from
IC1-15. IC1-3 (VDET) detects theAc voltage.The
feed-back signal fromPH3 for detecting the
secondary output Voltage is input to IC1-5. If IC1-
4 (OVP) is set toLow, IC1-8 (OUT) is also set to
Low and oscillation stops.
Primary Side Input voltage Detector
This detectoruses R14, R15 and R19 to detect the
primaryAC voltage and outputs signals controlled
by IC100, PH100 and Q101 tothecontrolIC (IC1).
Main Power Secondary Side
Rectifier and Smoother
This circuit rectifies and smoothes electric power
transmitted by the primary side to the secondary
side through the main transformersT1 andT2.
Line Filter
This line filter filtrates DC voltage having passed
through the secondary side rectifierand smoother
circuit (G) before it is supplied to the power unit.
Overheat Protector
This overheat protector circuit detects the
temperature ofthe heatsinkon whichQ4 toQ7 and
D4, D10 and D11 are mounted. When the
temperature exceeds about 110 , it isshort-circuit,
resulting in an alarm.
Secondary Voltage Detector
This circuit controls the secondary output voltage
based on the Vce voltage supplied by the power
unit (X68-1970-0x) and causes PH2 and PH3 to
output signals formaking the Vce voltage of Q1 to
Q10 of the power unit constant to the control IC
(IC1). Such control is turned on or off by the Vce
start controller block (K).
Vce Start Controller
This controller turns on or off the control for making
the Vce voltage constant using signals from the
control unit.
It turns offthe control when the signal is set to High
or turns onthe controlwhen thesignal is set toLow.
Table 5below shows the Vcevoltage ofeachtype.
Model Vce voltage
20V About 3.5V
36V About 4.5V
60V About 4.5V
Table 5
PDS-20-18(K)1,1(98.12.317:07 y[W 10

Primary Side
Control Circuit
ST2
ST1
VCE Detection
CT
SENSE
V OUT
OVP
OCP A/D
Preset
D/A
Shunt POWER SUPPLY UNIT
CONTROL UNIT
CPU UNIT
PANEL UNIT
MOTHER UNIT
OHP
CPU
I/O Control
I/O OptionBoard
I DISP
V DISP
Set Up
Switch
R/E
ALM
Sub Power
RCC
PRI
RSE
N/F
NFB AC UNIT
CV
CC
R/L
S
Shut Down Circuit
FAN
VIN
PDS20-18/PDS36-10/PDS60-6
11
PDS BLOCK DIAGRAM
PDS-20-18(K)1,1(98.12.317:07 y[W 11

ENC
P_SW
LED
D-DRU
Set Up Volume
Switch LED
7-Segment LED Driver
IC1,2
Rotary Encoder
S11
Panel Switch
OVP Volume
VR1
7-Segment LED
CPU UNIT
PANEL UNIT (X66-1600-00)
(X77-2110-00)
CONTROL UNIT
(X77-2120-00)
PDS20-18/PDS36-10/PDS60-6
12
BLOCK DIAGRAM
PDS-20-18(K)1,1(98.12.317:07 y[W 12

Sub-Power
Switching
MAIN SWITCH
Control
MAIN AC
Main Power
Control
AC Unit
CPU Unit
Sub-Power
Control
Secondary Side
Voltage Detector
PH2,D3.4
IC1,D7.10 T1
Q1
Q2,PH1,D6
PH1,IC2
(C)
(D)
Trip +
Control Unit
(B) D1
(A)
Rectifier &
Smoother
Rectifier &
Smoother
Rectifier &
Smoother
Rectifier &
Smoother
Rectifier &
+ 15V
Smoother
Main Power Primary Side
Rectifier &
Smoother
D100
D11.12
D13.14
D5
(J)
(I)
(H)
(G)
(F)
Power &
Control Unit
Power &
Control Unit
MOTHER UNIT (X67-1420-0X)
PDS20-18/PDS36-10/PDS60-6
13
BLOCK DIAGRAM
PDS-20-18(K)1,1(98.12.317:07 y[W 13

Primary Overvoltage
Detection
IC4(1/2), Q18
Vce Voltage
(AC UNIT)
Primary Input
(AC UNIT)
Overcurrent
Detection Circuit
Q15
Drive Circuit
Power Control
Bleeder Circuit
Q14,16,17,19
Q1~10
Q11~13
IC3(1/2)
MAX CC
Error Amp
IC4(2/2)
Current Detection
Circuit
R46,IC1
Voltage Regulator
IC2
+5 +15 -15
Bleeder Circuit
Q20
Control
(CONTROL UNIT)
CC Monitor
(CONTROL UNIT)
OUTPUT-
OUTPUT +
+15 -15 GND -3.5V
MOTHER UNIT
OCP
Primary OVP
Overheat Detection
TS1
OHP
(CONTROL UNIT)
POWER SUPPLY UNIT (X68-1970-0X)
PDS20-18/PDS36-10/PDS60-6
14
BLOCK DIAGRAM
PDS-20-18(K)1,1(98.12.317:07 y[W 14

Secondary
Voltage Detector
Main Power
Switching
Main Power
Control
Primary Side
Input Voltage Detector
Primary Side
Current Detector
Line
Filter
Protector
Over
Heart
MAIN AC
T1
T2
+15V
Mother Unit
Vce Voltage
Power Unit
Mother Unit
Power Unit
Line
Filter
L3 D4 T3
Q4..7
D18.19.20 L5
IC1,PH1.2.3
IC100,PH100
(A) (B) (C)
(D)
(F) (E)
(G) (H)
TS1
(I)
IC2,PH2.3
(J)
Q102.103.104,PH1
(K)
Vce Start
Controller Start/Stop
Cnotrol Unit
Main Power
Secondary Side
Rectifier &
Smoother
Main Power
Primary Side
Rectifier
AC Unit
(X68-1980-01,03,05,07)
AC UNIT (X68-1980-00,02,04)
OHP
Power Unit
PDS20-18/PDS36-10/PDS60-6
15
BLOCK DIAGRAM
PDS-20-18(K)1,1(98.12.317:07 y[W 15

Input Port
IC7,8
Reference DAC
IC12
Outpot Port
OUTPUT ON/OFF
Isolation
EEPROM
IC9
Compalator
IC16 Mon. DAC IC14
DATA
CLOCK
Error Amp
IC105
Monitor Amp
IC107
Reference Amp
IC106
Alarm Circuit
Q108,PH101 OVP Compalator
IC101
OHP
OCP
Pri.OVP
(POWER UNIT)
Pri.OHP
(AC UNIT)
CC Monitor
M/S Reference
Set Up VR
(PANEL UNIT)
+ Sensing
- Sensing
CC Status
Voltahe
Regulator
IC112,113
+15 -15
+5 -5
CPU
+5 GND
D_IN
D_OUT
(CPU)
External
OUTPUT ON/OFF
Trip
(MOTHER UNIT)
Control
(MOTHER UNIT)
+5
CPUGND +15 -15
CONTROL UNIT (X77-2120-0X)
PDS20-18/PDS36-10/PDS60-6
16
BLOCK DIAGRAM
PDS-20-18(K)1,1(98.12.317:07 y[W 16

D_IN
ROM
IC20
CONTROL UNIT
(X77-2120-0x) Rotary Encoder
S11 S1~S10
Interruption
Processing
IC21,22
Panel Switch
CPU
IC1,2,4,5,7,13
RAM
IC15
Input Port
IC9,14
OUTPUT:LED
Latch Circuit
IC6,8,12
OUTPUT PORT
Display
Drive
IC1,2
Switch
LED
LED
Option Board
X72-1380-00
X72-1380-01
X72-1460-00
P_SW
X66-1600-00
D_OUT
O_DATA
D_DRU
X77-2110-00
CPU UNIT (X77-2110-00)
PDS20-18/PDS36-10/PDS60-6
17
BLOCK DIAGRAM
PDS-20-18(K)1,1(98.12.317:07 y[W 17

PDS20-18/PDS36-10/PDS60-6
18
ADJUSTMENT
Toobtainthe bestperformance,periodically calibrate
the unit. Sometimes, only one mode need be
calibrated, while at othertimes, all modes should be
calibrated. When one mode is calibrated, it must be
noted that the other modes may be affected. When
calibrating all modes, perform the calibration in the
specified sequence.
The following calibration required an accurate
measuring instrument and an insulated adjusting flat
blade screwdriver.
If they are not available, contact your dealer. For
optimumadjustment,turn the poweron and warm up
the unit sufficiently (more than 30 minutes) before
starting. Before calibrating the unit check the power
supply voltage.
TEST EQUIPMENT REQUIRED
The following instrument or their equivalent should
be used for making adjustment.
Test Equipment Model Maker
Multi-meter 34401A HP
Shunt Register RUG-Z-xxx PCN
SHUNTREGISTER
RUG-Z-100-0.1
100[ ]RUG-Z-1R-0.1
10[ ]
PDS20-18
PDS36-10
PDS60-6
1-1. Voltage
Turn on the POWERswitch while pressing thePRESET2,KEYLOCK/LOCAL and FAST/SLOWkeys. (By
this, the PDS unit starts up in the adjustment mode.)
Connect the multi-meter with the output terminals on the rear panel.
1-2. Voltage REF Offset
1. Press the VOLTAGE key. (The VOLTAGELED goes on.)
2. Press thePRESET1 key. (ThePRESET1LED goes on.)
3. Press the OUTPUTkey. (The OUTPUTLED goes on.)
4. Adjust the voltage with the rotary encoder so that the multi-meter connected with output
terminal reads 1 mV.
5. Press the MEMORYkey. (ThePRESET1 toPRESET3LEDs go on.)
6. Press thePRESET1 key. (ThePRESET1LED goes on.
1-3. Voltage REF Gain
1. Press the Voltage key. (ThePRESET2LED goes on.)
2. Press thePRESET2 key. (ThePRESET2LED goes on.)
3. Adjust the voltage with the rotary encoder so that the multi-meter connected with output
terminal reads following table.
Model Setting[V] Range[mV]
PDS20-18 20.500 1
PDS36-10 36.900 1
PDS60-6 61.500 1
4. Press the MEMORYkey. (ThePRESET1 toPRESET3LEDs go on.)
5. Press thePRESET2 key. (ThePRESET2LED goes on.)
1-4. Voltage Monitor Offset
1. Press the VOLTAGE key. (The VOLTAGELED goes on.)
2. Press thePRESET3 key. (ThePRESET3LED goes on.)
3. Wait until operation becomes stable (for about ten seconds).
4. Press the MEMORYkey. (ThePRESET1 toPRESET3LEDs go on.)
5. Press thePRESET3 key. (ThePRESET3LED goes on.)
PDS-20-18(K)1,1(98.12.317:07 y[W 18

PDS20-18/PDS36-10/PDS60-6
19
ADJUSTMENT
1-5. Voltage Monitor Gain
1. Press the VOLTAGE key. (The VOLTAGELED goes on.)
2. Press the KEYLOCK/LOCAL key.
3. Wait until operation becomes stable (for about ten seconds.)
4. Press the MEMORYkey. (ThePRESET1 toPRESET3LEDs go on.)
5. Press the KEYLOCK/LOCAL key.
6. Press the OUTPUTkey. (TheOUTPUTLED goes ON.)
2-1. Current
Connect the shunt resister with the output terminal.
Connect the multi-meter with the shunt resister.
2-2. Current Ref Offset
1. Press the OUTPUTkey. (The OUTPUTLED goes on.)
2. Press the CURRENTkey. (The CURRENTLED goes on.)
3. Press the PRESET1 key. (ThePRESET1LED goes on.)
4. Adjust the voltage at the shunt resister connected with the output terminal to the value shown
below using the rotary encoder.
Model Adjustment
Value[V]
Range[mV]
PDS20-18 00.1
PDS36-10 00.1
PDS60-6 01
5. Press the MEMORYkey. (ThePRESET1 toPRESET3LEDs go on.)
6. Press thePRESET1 key. (ThePRESET1LED goes on.)
2-3. Current Ref Gain
1. Press the CURRENTkey. (The CURRENTLED goes on.)
2. Press thePRESET2 key. (ThePRESET2LED goes on.)
3. Adjust the voltage at the shunt resister connected with the output terminal to the value shown
using the rotary encoder.
Model Adjustment
Value[V]
Range[mV] Setting[A]
PDS20-18 1.850 1 18.50
PDS36-10 1.030 110.30
PDS60-6 0.620 16.20
PDS-20-18(K)1,1(98.12.317:07 y[W 19

PDS20-18/PDS36-10/PDS60-6
20
ADJUSTMENT
4. Press the MEMORYkey. (ThePRESET1 toPRESET3LEDs goon.)
5. Press thePRESET2key. (ThePRESET1LED goes on.)
2-4. Current Monitor Offset
1. Press the CURRENTkey. (The CURRENTLED goes on.)
2. Press thePRESET3 key. (ThePRESET3LED goes on.)
3. Wait until operation becomes stable. (For about ten seconds.)
4. Press the MEMORYkey. (ThePRESET to1 PRESET3LEDs go on.)
5. Press thePRESET3 key. (ThePRESET3LED goes on.)
2-5. Current Monitor Gain
1. Press the CURRENTkey. (The CURRENTLED goes on.)
2. Press the KEYLOCK/LOCAL key.
3. Wait until operation becomes stable. (For about ten seconds)
4. Press the MEMORYkey. (ThePRESET1 toPRESET3LEDs go on.)
5. Press the KEYLOCK/LOCAL key.
6. Press the OUTPUTkey. (The OUTPUTLED goeson.)
3. Over Voltage Protect
Before starting OVP adjustment, disconnect the shunt resister from the output terminals.
1. Rotate the OVP control fully counterclockwise to the minimum position.
2. Press the OUTPUTkey. (The OUTPUTLED goes on.)
3. Press the OVP key.
4. The 7-segment LED begins to count. Wait untilthe value stops changing.
5. OVP adjustment is completed.
PDS-20-18(K)1,1(98.12.317:07 y[W 20