DAHUA DH1715A User Guide

Model

DH1715A

Dual

Channel

---

Channel

Regulated

Voltage/Current

User

’’’

sss

Power

Manual

Supply

hhh

uauaua

Company

DaDaDa

Electronic

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Electronic

Instrument

ininin

Beijing

Description

1. Operating Features

2. Operating Principle

Structure Features

CONTENTS

Applications

Maintenance

Completeness of the Instrument

Storage

Guarantee

DESCRIPTION

Mode l

DH1715A-3

32V-2A

DH1715A-5

32V-3A

INPUT

Input P ower S upply

2 2 0V ± 10% 50Hz ± 5%

P ower D issipation (200VAC), R ate L oad

≤

300VA

OUTPUT

O utput

ltage (10-turn)

0-32V

T heor eti calValue ofVoltage resolution

5mV

O utput C urrent(1-turn)

0-2A

0-3A

CV FEATURE

Adj. Ratio

S ource E ffect (line regulation)(for 0-100% change of output current)

1 × 10

-5

+1mV

L oad E ffect

1 × 10

-5

+2mV

R ipple and N oise(5Hz-1MHz) r.m.s

1mV

Typ

e.Value

of Temp. Coe.

2 × 10

-4

℃

R emote C ontrol ( C on trolVol t./O utput

Volt

about 10V/32V

CC FEATURE

Adj. Ratio

Source Effect (line regulation)(for ± 10% change of line volt)

2mA

L oad E ffect(load regulation) (for 0-100% chang e of load resistance)

10mA

R ipple and N oise (5Hz-1mHz) r.m.s

1mA

R emote C ontrol ( C on.

Voltage/

Output C u r rent)

about 10V/2A 10V/3A

CV Mode

ndication

CC M ode

ndication

Operating

emperature Rang

0-40 ℃

R elative A mbient O perating H umidity R ange

20-90%RH

S torageTemperature and H umidity R ange

unforced air cooling

C ooling M ethod

positive or negative grounded

P olarity of O utput

oltage

DESCRIPTION

The Model DH1715A Dual - Channel Regulated V oltage/Current Power Supply is an automatic switching type of high accuracy CV/CC power supply with a 3

digits display

1/2

meter on the front panel. The output voltage and the output current can be displayed by ON /OFF switch on the front panel. This instrument provides a preset circuit and an output switching circuit, the output switch is an electronic type, which does not generate chattering and noise. When the output switch is set to “ OFF ” state, the value indicated by the output voltmeter cor responds to the position of the voltage setting knob so as to preset the voltage. Press “ OUTPUT ” switch, the output voltage is available from “ OUTPUT ” terminal. This instrument has function of the remote-controlled voltage. The input socket on the rear panel is controlled remotely. Please carefully read this instruction manual before use the power supply.

OPE

1.1.1.

OPE

RRR

ATING

FEATURES

Continue:

Model

DH1715A-3

32V-2A

DH1715A-5

32V-3A

VOLTMETER

Range Selection

Accuracy of Voltmeter

± (0.5%rdg + 3dgts, at 20 ± 2 ℃ and < 80%RH

Maximum Allowable Application

Voltage

DC AMMETER

Full Scale (Fixed Range)

Ammeter Accuracy(at20 ± 2 ℃ and<80%RH)

± 1rdg + 5dgts

Temperature Coe

(+400 × 10

-6

) / ℃ full- scale + the accuracy mentioned

above

Zero Drift

Not greater than 3dgts within 0-40 ℃

Input Fuse

Output Fuse

Weight

≤ 8kg

External Dimensions

305(L) × 200(W) × 170(H)mm

Reliability of the Instrument

MTBF ( θ ) ≥ 5000 hours

Remote

Control

Signal

Transformer

Relay Switching and

Aux. Supply Circuit

Output Switch Circuit

Reference

Voltage

Remote

Control

Circuit

Voltage

Sampling

Control

Circuit

Rectify

and Filting

Series

Setting

Amplify

Gate

Diff

Ampl

Diff.

Ampl

A/D

Conv

220V

Meter Circuit

Current

Sampling

Figure 1

OPE

2.2.2.

OPE

RRR

ATING

PRINCIPLE

The feature of this power supply is that the output voltage signal of constant V oltage circuit and the output current signal of constant current circuit both are applied to the “ GATE ” circuit at the same time. According to requirement of the load, the pow er supply is determined to operate in the CV mode or in the CC mode, the automatic switching of the regulated voltage and the regulated current can solve the problems of over — current protection of the regulated power supply and the over — voltage protection of the regulated current power supply.

CONTROL

CIRCUIT:

It is an adjustable reference voltage generator. The output current

and voltage depend on setting the reference voltage.

2.1

Description

Constant

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Constant

Voltage

---

Voltage

Mode

The reference output voltage circuit is applied to the negative input terminal of a CV error amplifier, the error voltage from the voltage sampling resistor is applied to the positive input terminal of the CV error amplifier. The error signals of both vol tages are compared each other and via the gate circuit by amplify then applied to the base of a regulated tube. The base current of the regulator tube is changed, then a stabilized output voltage can be obtained ,

the adjustment of the output voltage is re alized by setting the voltage potentiometer on the

front panel.

2.2

Description

Constant

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Constant

Current

---

Current

Mode

The reference voltage from the control circuit is applied to the negative input terminal of a CC error amplifier, the current signal from A/V conversion is applied to the positive input terminal of the CC error amplifier. Both signals are compared each other and then amplified to control the base voltage of the regulator tube to reach a stable current output.

CV/CC

2.3

CV/CC

2.3

Conversion

mode

---

CVCVCV

mode

into

mode

CCCCCC

mode

Setting CC potentiometer, a preset current value is provided as required, the resistor load is reduced, the output current is increased. When the output current reaches the preset constant current value, the output voltage is reduced. When the power supp ly is power supply is operating in the constant - current mode, even of the resistor load value is reduced to zero ( in short circuit state), the output current can not be increased, it always keeps pre - setting value constantly; that means this instrument can automatically be converted from constant - voltage mode to constant current mode so as to protect the load from over - current. It is an automatic CV/CC crossover system type of power supply.

The Figure 2 shows operating points and operating domain related to the load lines. The preset output voltage is

when RL=10 Ω

10V,

the limited current is 2A, the operating point in non--load is atA,

operating point B, and when RL=5 Ω , operating point is at C. The

operating point moves from C to D ,if the resistor load is reduced from RL=5 Ω to 2.5 Ω ,the instrument operation is changed from the constant-voltage domain into the constant — current domain. Point C is called “ Crossover Point ” owing to change modes.

Wen

the resistor load

(RL) is 2.5 Ω , the output voltage is I. RL=2 × 2.5=5V .

CC/CV

2.4

CC/CV

2.4

Conversion-Constant

Current

Mode

into

Constant-Voltage

into

Constant-Voltage

Mode

Setting CV potentiometer, a preset value applied as required. When the output voltage reaches the preset constant voltage value, then output current is reduced.

When the output current is 2A the resistor load is 0 Ω , operating point is E. While the resistor

load is increased to 2.5 Ω , the operating point moves from E to D. When the operating point is increased to 5 Ω

the operating point moves from D to C. While the resistor load further is

increased to 10 Ω , the operating point moves from C to B. In this case, the instrument is converted to the constant - voltage domain. When the resistor load is increased continuously to an open circuit, the operating point moves from B to

. Generally, the voltage applied to the load is not more than the preset voltage. The instrument can convert from the CC mode to the

mode in order to protect the load. The point C serves as a crossover point.

+ 9 hidden pages

DAHUA DH1715A User Guide

Specifications and Main Features

Frequently Asked Questions

User Manual

Description

CONTENTS

DESCRIPTION