Tonghui TH2821A Operation Manual

TH2821A

Portable LCR Meter

OPERATION MANUAL

English

November 2005

st

1

© Copyright 2005 Changzhou Tonghui Electronic Co., Ltd.

Edition Rev 1.0.0

All rights reserved.

TH2821A OPERATION MANUAL

Contents

Contents............................................................2

How to Contact Us.......................................3

Incoming Inspection.....................................4

Notes on Use ...............................................5

Warranty:....................................................6

Chapter 1 Overview............................................7

1.1 Introduction...........................................7

1.2 Main Functions.......................................7

1.3 Specifications ........................................9

1.4 Environment Requirements...................12

Chapter 2 Panel Illustration..............................13

2.1 LCD Display Illustration.........................13

2.2 Keyboard Illustration............................15

Chapter 3 Operation.........................................17

3.1 Power on.............................................17

3.2 How to operate....................................18

3.2.1 First Key Functions .....................18

3.2.2 Second Key Functions:................20

3.3 Battery recharge..................................30

3.4 Clearing Instruction..............................31

Appendix .........................................................32

2

TH2821A OPERATION MANUAL

How to Contact Us

Changzhou Tonghui Electronic Co., Ltd.

Address: No. 3, Tianshan Road, New District,

Changzhou, Jiangsu, China

Tel: [phone]
Fax: [phone]

http://www.tonghui.com.cn
http://www.tonghui.cn
Email: [email protected]

3

TH2821A OPERATION MANUAL

Incoming Inspection

Inspect the shipping container for damage. The contents of
the shipment should be listed as follows. If the contents are
incomplete, if there is damage or defect, please contact
our company or your nearest Sales and Service Office.

Accessories

TH26028 DC Power Adapter 1
TH26027 4 terminal Kelvin test clip leads 1
LH-200H7C rechargeable battery (inside) 1

User Manual 1
Options

TH26029 SMD component test fixture

4

TH2821A OPERATION MANUAL

Notes on Use

z This meter is only for indoor use.
z Turn off the TH2821A while switching the power supply

between battery and DC adapter or replacing the
battery.

z Although internal circuit protection is provided, DC

voltage or current may damage TH2821A. Before you
measure a capacitor, be sure the capacitor is fully
discharged.

z Charging may disturb measurement result sometimes.
z Nickel Metal Hydride rechargeable battery can be used

for the power supply. TH2821A will not work normally
when battery voltage is less than 6V.

z The 12V AC to DC adaptor is recommended to be used

for TH2821A power supply.

z Perform Open and Short corrections for accurate

measurement especially when test fixture is changed.

z The functions locked with password are not accessible

by users.

5

TH2821A OPERATION MANUAL

Warranty:

This instrument product is warranted against defects in
material and workmanship for a period of two years from
the date of shipment. During the warranty period, Our
company will, at its option, either repair or replace
products which prove to be defective. For warranty service
or repair, this product must be returned to a service facility
designated by our company.

Warranty limitation

The foregoing warranty shall not apply to defects resulting
from improper or inadequate maintenance by Buyer,
Buyer-supplied software or interfacing, unauthorized
modification or misuse, or improper site preparation or
maintenance.

6

Chapter 1 Overview

Thank you for purchasing our product. To get the maximum
performance from the instrument, please read this manual
first, and keep this manual at hand.

1.1 Introduction

TH2821A is a microprocessor-controlled portable meter with
low power consumption. It can measure six basic parameters,
they are inductance L, capacitance C, resistance R,
impedance |Z|, dissipation factor D and quality factor Q.
TH2821A can fulfill the measurement needs of various
component manufacturers and maintenance technicians.

1.2 Main Functions

1． Test Parameter

L-Q, C-D, R-Q and Z-Q.

2． Correction

OPEN: multi-frequency correction of open circuit;
SHORT: multi-frequency correction of short circuit.

3． Display Mode

Direct —— direct measurement value;

∆ —— absolute deviation;
∆% —— percent deviation.

4． Range Hold

When measuring a large number of components with
the same nominal value, this function can effectively
improve the measuring rate.

TH2821A OPERATION MANUAL

5． Comparator Function

Built-in 4 Bins comparator: NG, P1, P2 and P3.

6． Equivalent Circuit Mode

Both parallel and series equivalent circuit modes can
be obtained.

7． Data Hold

This function can be used to freeze the current display
value.

8． Alarm Mode

NG, P1, P2, P3 and OFF modes can be selected.

8

TH2821A OPERATION MANUAL

1.3 Specifications

Parameter L-Q, C-D, R-Q and Z-Q

Frequency 100 Hz, 120 Hz , 1 kHz and 10 kHz

Accuracy

Display

Measurement

Range

Test Level

(Range Auto

and Open

Circuit)

Ranging Mode Auto and Hold

Basic Accuracy: 0.3%
5 digits display for both primary and secondary

parameters

100 Hz,120 Hz

L

1 kHz,10 kHz
100 Hz, 120Hz

C

1kHz,10 kHz

R, |Z|

D, Q 0.0001 – 9999

10kHz
120Hz

1kHz

100Hz

0.0001 Ω - 999.9 MΩ

0.0001% - 9999%

∆%

0.1 Vrms (1±15%)

0.3 Vrms (1±15%)

0.42 Vrms (1±15%)

1 µH – 9999 H

0.1 µH – 999.9 H
1 pF – 9999 µF

0.1 pF – 999.9 µF

Equivalent

Circuit

Display

Correction Open and Short Zeroing

Rate Approx. 3 meas/sec

Termina ls 5 terminals

Parallel and Series

Direct, ∆ABS and ∆%

9

TH2821A OPERATION MANUAL

Comparator

Limit Setup

Range

Alarm Mode NG, P1, P2, P3 and OFF

Power Supply

4 Bins：NG, P1, P2 and P3

-9999% - 99999%

∆%

L
C

Nominal

9V rechargeable battery or DC12V(100 mA)
adapter

R
Z

(Continued)

0.0001 µH – 99999 H

0.0001 pF – 99999 µF

0.0001 Ω - 99999 MΩ

0.0001 Ω - 99999 MΩ

Low Battery

Indication

Power

Consumption

Auto Power

Off time

Weight Approx. 400 g

Dimensions 200mm(L) × 95mm(W) × 40mm(D)

Approx. 6V

Normal: Approx. 25 mA
Auto power-off: Approx. 500 nA

Approx. 5 minutes

Table 1-1 Specifications

10

TH2821A OPERATION MANUAL

*Note：

Primary parameter accuracy(Ae)

C： Ae = 0.3%(1+Cx/C
L： Ae = 0.3% (1+ Lx/L
Z： Ae = 0.3% (1+ Zx/Z
R： Ae = 0.3%(1+ Rx/R

Max and Min values are as follows：

Parameter Range Auto

C
C
L

L

Z

Z

Here：Z

max

= R

Secondary parameter accuracy

De= Ae/3 when D
De= Ae(1+Dx)/3 when Dx＞0.1

e

×

µ1

DQ

×

±

Q

=

max+Cmin/Cx

max

max

max

max

150pF/f

min

159H/f

max

0.32mH/f

min

max

min

; Z

= R

max

min

ex

when Qx·De<1

DQ

ex

)

+ L

)

min/Lx

+ Z

)

min/Zx

+ R

)

min/Rx

80µF/f

1MΩ

1.59Ω

, Frequency unit: kHz.

min

≤0.1

x

11

TH2821A OPERATION MANUAL

1.4 Environment Requirements

1． Please do not operate TH2821A under the following

environment conditions, as any of them will directly
affect measuring precision or damage the meter:

z Please do not operate the instrument in places

where is dusty, vibrant, under direct sunlight, or
where there is corrosive air.

z Although TH2821A has been specially designed

for reducing the noise caused by AC power, the
environment with low noise is still recommended.
If this can not be arranged, please make sure to
use power filter for the AC-DC adaptor.

2． The TH2821A must be operated under the following

environment conditions:
Temperature: 0°C ~ 40°C,
Humidity: ≤ 90% RH at 40°C.

3． Storage Temperature: -25°C ~ 50°C.

12

TH2821A OPERATION MANUAL

Chapter 2 Panel Illustration

2.1 LCD Display Illustration

Figure 2-1 LCD Display

13

TH2821A OPERATION MANUAL

No. Description No. Description

Battery Power

1

Indicator
Remote

2

Indicator
Beeper

3

Indicator
Series/Parallel

4

Indicator
Comparator

5

Indicator
Secondary

6

Parameter
Indicator
Secondary

7

Parameter
Display

Table 2-1 LCD Description

Others:

DH: Data hold indictor
CAL: Correction function indictor
MENU: Menu operation indictor

8 Unit Indicator
9 Ranging Mode Indicator

Primary Parameter

10

Display

11 Frequency Indicator

Primary Parameter

12

Indicator

13 2nd Function Indicator

DC Adaptor Power Supply

14

Indicator

14

TH2821A OPERATION MANUAL

2.2 Keyboard Illustration

CLEAR

①

POWER

PARA

ESC

EQU

DHSHIFT

▲

Figure 2-2 Keyboard

ÂConvention：

Key Function Conventions

st

1

function: PARA

2nd function: CLEAR

rd

function: }

3

②

15

LIMIT

U

▲

BUZZER

V

③

MENU

FREQ

ENTER

DISPLAY

AUTO

④

⑤⑥⑦⑧

TH2821A OPERATION MANUAL

SHIFT+

Key

CLEAR

MENU

DISPLAY

Function

Correction
key
Sorting Limit
Setup
Auxiliary
Menu
Display Mode
Selection
Alarm Mode
Setup
Equivalent
Circuit

No. Key Function

1

○

2

○

3 U

○

4

○

5

○

6 V

○

7

○

8

○

rd

The 3

POWER

PARA

FREQ

AUTO

DH

SHIFT

Functions：

Power
On/Off
Parameter
Selection

Range Up LIMIT
Frequency

Selection
Range Auto
Selection

Range Down BUZZER
Data Hold EQU

2nd Function

Table 2-2 Key Description

}, o, q, p, r and x are valid during Menu

setup and Data input operations.

16

TH2821A OPERATION MANUAL

Chapter 3 Operation

3.1 Power on

1. Press POWER key to turn on TH2821A.

2. The operation system version will be displayed.

3. At last the instrument enters the measurement state.

Figure 4-1 Measurement Display

Measurement display description:

1. Battery Supply 3. Beeper ON

4. Series Circuit 5. Sorting Result: P1

6. Parameter D 7. Secondary parameter

8. Unit 9. Range 0 (Auto)

10. Primary parameter 11. Frequency: 1 kHz

12. Parameter C

17

TH2821A OPERATION MANUAL

3.2 How to operate

3.2.1 First Key Functions

1. Parameter Setup：
Press PARA key to select the following measurement
parameter combinations：L-Q, C-D, R-Q and Z-Q.
Units Description:

L
C pF nF

R/|Z|

|Z| is the absolute value of impedance. Measurement
value of L, C or R may be positive or negative. Negative
capacitance value means that the device under test is
actually an inductor; also negative inductance value means
that the device under test is actually a capacitor. In theory
R should be positive constantly, under some condition, R
may be negative due to over zero correction. Please carry
out correct zero correction.
The maximum number of display digits is 5, but 5-digit is
not always available and 4-digit is displayed sometimes.
The conversion is described in the following description:
From 4-digit to 5-digit:

When the first 2 digit of current value is less than 18.
From 5-digit to 4-digit:
When the first 2 digit of current value is more than 20.

2. Frequency Setup:
Use FREQ key to select the following test frequencies in
turn: 100 Hz, 120 Hz ，1 kHz and 10 kHz.

µH

Ω

Table 4-1 Units

mH H

µF

kΩ MΩ

18

TH2821A OPERATION MANUAL

3. Range Setup:

U, V and AUTO keys are used to set the measurement

range. AUTO key toggles ranging mode between “Auto”

and “Hold”. U and V keys are used to increase or
decrease the measurement range, if the current ranging
mode is “Auto”, then the ranging mode is changed to
“Hold” at the same time.

* Note：

When ranging mode is set to HOLD, the measurement
range is fixed at current range. Overload symbol “-----” will
be displayed if the impedance under test exceeds the
current effective measurement range or display range.

Range

No.

0

1

2
3

4

Range

Resistor

100kΩ

10kΩ

1kΩ

100Ω

20Ω

Table 4-2 Ranges

Range

Up

Ï

20kΩ

Ï

2kΩ

Ï

200Ω

Ï

20Ω

Ï

Range

Down

Ð

18kΩ

Ð

1.8kΩ

Ð

180Ω

Ð

18Ω

Ð

19

TH2821A OPERATION MANUAL

* Note：

How to calculate the measurement range
Example: Assume capacitance C=210pF, dissipation D=0.0010 and
test frequency f=1 kHz.
Solution:

Z

X

From the Table 4-2, we can get the correct measurement range is
No. 2.

4. Data Hold

Press DH key to freeze the display, press DH key again to
release.

3.2.2 Second Key Functions:

1. Correction Function

z Press
z Press CLEAR key to enter the correction function, the

u key to select the second function, “SHIFT”

will be lighted on the screen.
following information will be displayed on the screen.

1

+=

RZ

XX

2

fCj

π

X

1

=≈

2

fC

π

X

1

−

9

××××

1021010001416.32

Ω≈

9.757

Figure 4-2 Correction Display

20

TH2821A OPERATION MANUAL

z Clear (Clear) is displayed in the primary parameter

display area, OpeN (OPEN), Short (Short) or Quit (Quit)
will be displayed in the secondary parameter display
area.

* Note：

OpeN (OPEN), Short (Short) and Quit (Quit) are selected and
displayed automatically by the meter acco rding to th e impedance
value of the device under test.

z Press } key to cancel the correction operation and

return to the measurement state. Press
start the correction measurement.

z When correction measurement is finished, PASS or FAIL

will be displayed on the screen, see Figure 4-3

x key to

Figure 4-3 Open correction Passed

z Press

} key to abort the current correction data

measurement and return to the measurement. The
previous correction data will still be stored.

* Note：

1． The correction function must be used for accurate measurement.

The correction function can eliminate the stray admittance
(capacitance, and inductance) and the residual impedance
(resistance and reactance) induced by test f ixture, test leads and

21

TH2821A OPERATION MANUAL

instrument itself. Perform the correction operation again if the
measurement conditions are changed such as test fixture and
environment temperature.

2． It is recommended to perform the open and short correction at

the same time.

3． During short correction period, FAIL (F AIL) will be displayed in the

secondary parameter display area when short correction is failed.
Make sure that the measurement contacts are shorted reliably
and perform the short correction again.

4． TH2821A measures the correction data at all frequency points and

all measurement ranges. The correction data is stored in the
non-volatile memory . So you don’t have to perform th e correction
again, if the test conditions are not changed.

5． Open and short corrections are automatically selected by the

instrument according to the impedance value under test. If there
is a component in the fixture or if there is error with the
instrument, Quit (Quit) will be displayed in the secondary
parameter display area.

2. Equivalent Circuit

z Press

u key to select the second function, “SHIFT”

will be lighted on the screen.

z Press EQU key to select the Series or Parallel circuit

mode. (Refer to Figure4-1)

* Note：

1． The actual C, R and L are not the ideal pure C, R and L. Normally

an actual component can be regarded as the combination of an
ideal resistor and an ideal reactor in series or parallel circuit
mode.

2． TH2821A can convert between the two different equivalent

circuit modes using the following equations. The measurement
values of the two different circuit modes maybe different under
different quality factor Q (or dissipation factor D).

22

TH2821A OPERATION MANUAL

Capacitance Cp: from parallel to series

Cp

Capacitance Cs：from series to parallel

Inductance Lp：from parallel to series

Dissipation:

Series:

Circuit Mode：
Dissipation：

Series：

Circuit Mode：
Dissipation:

Paralle l:

Circuit Mode：

D

D

23

Rp

1

π

2

+=

PS

Cs

2 ==

π

SP

1

==

QRfC

PP

2

)1(

CDC

PS

22

)1(

DDRR

+=

Rs

1

CfRD

SS

Q

2

)1(1

CDC

+=

+=

SP

22

)1(

DDRR

Lp

Rp

π

fL

2

P

P

+=

PS

1

==

QR

2

)1(1

LDL

PS

22

)1(

DDRR

+=

Inductance Ls：from series to parallel

TH2821A OPERATION MANUAL

D

2

Lp Rp

R

1

S

==

QfL

π

S

2

)1(

LDL

+=

SP

)1(

DDRR

+=

SP

22

Circuit Mode：
Dissipation：

Parallel:

Here parameter with subscript s means the series mode,
parameter with subscript p means the parallel mode.

3. From the above equations, we can conclude that the conversion

between series and parallel is determined by D2 or Q2（Q=1/D）.
The value of D2 or Q2 directly determined the parameter values in

different circuit mode.
Example:
Three capacitors have the same series capacitance: Cs=0.1µF, but
their dissipations are different with each other: D1=0.0100,
D2=0.1000, D3=1.0000. According to the above equation, we can
get their capacitance in parallel mode:
Cp1 = 0.09999 µF
Cp2 = 0.09901 µF
Cp3 = 0.05000 µF
We can find that Cs is almost the same with Cp when D is very

small (Ｄ< 0.01), but when D is more than 0.01，Cp and Cs are
different obviously. For example: When D = 0.1，the difference is
1%，but when D = 1，the difference is almost 50%.

3. Alarm Setup

z Press

u key to select the second function, “SHIFT”

will be lighted on the screen.

24

TH2821A OPERATION MANUAL

z Press BUZZER, the following information will be

displayed on the LCD screen：

Figure 4-4 Alarm Setup

z Use

z Press

z press

4. Display Mode

z Press
z Press DISPLAY key to select the display mode: Direct,

rand q keys to select following alert modes in

turn.

OFF Alert off
P1 P1 alert mode
P2 P2 alert mode
P3 P3 alert mode
Ng NG alert mode

xto save the alert setup and return to the

measurement state.

} to abort the alert setup without change.

u key to select the second function, “SHIFT”

will be lighted on the screen.
Absolute deviation（∆）, Percent deviation（∆%）.

* Note：

1． Absolute deviation （∆）display mode

25

TH2821A OPERATION MANUAL

−=∆

−

Figure 4-5 Absolute deviation（∆）display mode

XX

Where Xx is the measurement value, X

stdx

is the standard value.

std

2． Percent deviation（∆%）display mode

Fixture 4-6 Percent deviation（∆%）display mode.

XX

=∆

stdx

X

std

26

%100% ⋅

TH2821A OPERATION MANUAL

5. Sorting Setup

 Key Convention：

Key Main Menu Data Input

r
q

p

o

x
}

z Press u key to select the second function, “SHIFT”
z Press LIMIT to enter the sorting setup, P1~ will be

z Use r, q to select the following sorting parameters:

Select the former item Select the left digit
Select the next item Select the right digit

Select parameter for
StD setup

Select parameter for

StD setup
Enter the sub menu

Return to the
measurement state

Increase the digit, move
the point left and set the
unit
Decrease the digit, move
the point right and set the
unit
Confirm the data input, and
return to the main menu

Return to the main menu

Table 4-4 Key convention in sorting setup

will be lighted on the screen.

flashing on the screen, and the value of P1~ is also
displayed.

P1_: Low limit of P1
P1~: High limit of P1
P2_: Low limit of P2
P2~: High limit of P2
P3_: Low limit of P3
P3~: High limit of P3

27

TH2821A OPERATION MANUAL

Q_: Low limit of Q
D~: High limit of D
StD: Standard value

z Press

z Press

} key to abort the sorting setup and return to

the measurement state.

x key to select a parameter and enter the

data input operation.

Figure 4-7 Sorting Limit Setup

z Use r, q keys to select a digit or the point.
z Use
z Press
z Press

z Select parameter STD to set the standard Value.

z Use r, q keys to select a digit, the point or the unit.
z Use
z Press

p,o keys to set the numeric value.

} to return to the main menu.
x to confirm and save the numeric data.

Figure 4-8 Standard Value Setup

p,o keys to set the numeric data and unit.

} to return to the main menu.

28

z Press

p

TH2821A OPERATION MANUAL

x to confirm and save the numeric data.

Sorting

Setu

N

D ≤ Dmax
Q ≥ Qmin

Y

P1min ≤ ∆% ≤ P1max

N

P2min ≤ ∆% ≤ P2max

N

P3min ≤ ∆% ≤ P3max

N

NG

END

Y

Y

Y

P1

P2

P3

Figure 4-8 Sorting Flow Chart

29

TH2821A OPERATION MANUAL

6. Other Functions：

z Press u key to select the second function, “SHIFT”

will be lighted on the screen.

z Press MENU key, APO will be flashing on the screen.

Current delay time is also displayed.

z Press

z Use p,o keys to select 5’, 10’, 20’,30’ or OFF.
z Press

x key to enter the auto power off function

setup, current delay time flashes on the screen.

x key to confirm the current delay time and

return to the main menu.

*Note：

When an external DC adapter is used, APO function is disabled
automatically.

z Use r, q keys to select “CAL” function.
z Press

3.3 Battery recharge

x key to enter the calibration function. This

function is protected with password and is not
available for users.

*Note：

The instrument will not be started, when the battery
is weakening. Recharge the battery immediately by using
DC Adaptor Power Supply.
z Battery Power Indicator will flash when charging.

30

TH2821A OPERATION MANUAL

z Charging may disturb measurement result sometimes.
z The battery must be 9V series Nickel Metal Hydride

rechargeable battery. For example GP20R8H and

LH-2007HC. 。
z 2~3 hours for charging and 5~6 hours for using.

3.4 Clearing Instruction

To clean the instrument, use a soft cloth slightly dipped in
water. Do not spray cleanser directly onto the instrument,
since it may leak into the cabinet and cause damage. Do
not use chemicals containing benzine, alcohol or aromatic
hydrocarbons.

31

TH2821A OPERATION MANUAL

Appendix

Message Code Table：

clear

OpeN

short

P1~

P1_

Mg

Q_

D~

Std

ApO

Cal

Psd

Alert

OM

Off

pass

faIl

Quit

Clear: Correction
Open: Open correction
Short: Short correction

—

: High limit of P1 Bin

P1
P1_: Low limit of P1 Bin
NG: No-Good
Q_: Low limit of quality factor
D_: High limit of dissipation factor
Std: Standard value (Nominal value)
APO: Auto Power Off
CAL: Accuracy Calibration
PSD: Password
Alert
ON
OFF
Pass
Fail
Quit

First Edition2005-11

32