Tonghui TH2821B Operation Manual

OPERATION MANUAL

English

February 2006

TH2821B

Portable LCR Meter

TH2821B OPERATION MANUAL

2

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........................................ 8

1.4 Environment Requirements .................. 10

Chapter 2 Panel Illustration............................. 11

2.1 LCD Display Illustration ........................ 11

2.2 Keyboard Illustration ........................... 13

Chapter 3 Operation........................................ 14

3.1 Power on............................................. 14

3.2 How to operate ................................... 15

3.2.1 Key Functions ............................ 15

3.3 Battery Replacement ........................... 21

3.4 Clearing Instruction ............................. 22

Appendix......................................................... 23

TH2821B OPERATION MANUAL

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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 D

C Power Adapter 1
TH26027 4 terminal Kelvin test clip leads 1
1604A 9V battery 1

User Manual 1

Options

TH26029 SMD component test fixture

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Notes on Use

z This meter is only for indoor use.
z Turn off the TH2821B 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 TH2821B. Before you
measure a capacitor, be sure the capacitor is fully
discharged.

z Take out the battery when the meter is not in use for

more than 3 months.

z A single standard 9V battery can be used for the power

supply. TH2821B will not work normally when battery
voltage is less than 6V.

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

for TH2821B 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.

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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.

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

TH2821B 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.
TH2821B 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;

4． Range Hold

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

5． Equivalent Circuit Mode

Both parallel and series equivalent circuit modes can

TH2821B OPERATION MANUAL

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be obtained.

6． Data Hold

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

1.3 Specifications

Parameter L-Q, C-D, R-Q and Z-Q
Frequency 100 Hz, 120 Hz and 1 kHz

Accuracy

Basic Accuracy: 0.3%

Display

5 digits display for both primary and secondary
parameters

100 Hz,120 Hz

1 μH – 9999 H

L

1 kHz

0.1 μH – 999.9 H

100 Hz, 120Hz

1 pF – 9999 μF

C

1kHz

0.1 pF – 999.9 μF

R, |Z|

0.0001 Ω - 999.9 MΩ

D, Q 0.0001 – 9999

Measurem
ent Range

Δ%

0.0001% - 9999%

1kHz

0.3 Vrms (1±10%)

Test Level

(Range

Auto and

Open

Circuit)

100Hz
120Hz

0.3 Vrms (1±15%)

Ranging

Mode

Auto and Hold

Equivalent

Circuit

Parallel and Series

Display Direct

TH2821B OPERATION MANUAL

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(Continued)

Correction Open and Short Zeroing

Rate Approx. 3 meas/sec

Termina l s 5 terminals

Power Supply 1604 9V battery or DC12V(100 mA) adapter

Low Battery

Indication

Approx. 6V

Power

Consumption

Normal: Approx. 30 mA
Auto power-off: Approx. 500 nA

Auto Power

Off time

Approx. 30 minutes

Weight Approx. 400 g

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

Table 1-1 Specifications

*Note：

Primary parameter accuracy(Ae)

C： Ae = 0.3%(1+Cx/C

max+Cmin/Cx

)

L： Ae = 0.3% (1+ Lx/L

max

+ L

min/Lx

)

Z： Ae = 0.3% (1+ Zx/Z

max

+ Z

min/Zx

)

R： Ae = 0.3%(1+ Rx/R

max

+ R

min/Rx

)

TH2821B OPERATION MANUAL

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Max and Min values are as follows：

Parameter Range Auto

C

max

80μF/f

C

min

150pF/f

L

max

159H/f

L

min

0.32mH/f

Z

max

1MΩ

Z

min

1.59Ω

Here：Z

max

= R

max

; Z

min

= R

min

, Frequency unit: kHz.

Secondary parameter accuracy

De= Ae/3 when D

x

≤0.1

De= Ae(1+Dx)/3 when Dx＞0.1

Qe=

ex

ex

DQ

DQ

×

×

±

μ1

when Qx·De<1

1.4 Environment Requirements

1． Please do not operate TH2821B 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 TH2821B 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 TH2821B 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.

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Chapter 2 Panel Illustration

2.1 LCD Display Illustration

Figure 2-1 LCD Display

TH2821B OPERATION MANUAL

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No. Description No.

Description

1

Battery Power
Indicator

8 Unit Indicator

2

Remote
Indicator

9 Ranging Mode Indicator

3

Beeper
Indicator

10

Primary Parameter
Display

4

Series/Parallel
Indicator

11 Frequency Indicator

5

Comparator
Indicator

12

Primary Parameter
Indicator

6

Secondary
Parameter
Indicator

13 2nd Function Indicator

7

Secondary
Parameter
Display

14

DC Adaptor Power Supply
Indicator

Table 2-1 LCD Description

Others:

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

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2.2 Keyboard Illustration

Figure 2-2 Keyboard

No. Key Function

○

1

POWER

Power On/Off

○

2

PAR A

Parameter Selection

○

3

FREQ

Frequency Selection

○

4

CLEAR

CLEAR Selection

○

5

RANGE

Range Selection

○

6

AUTO

Range Auto Selection

○

7

DH

Data Hold

○

8

EQU

Series/Parallel
Indicator

Table 2-2 Key Description

TH2821B OPERATION MANUAL

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Chapter 3 Operation

3.1 Power on

1. Press POWER key to turn on TH2821B.

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

TH2821B OPERATION MANUAL

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3.2 How to operate

3.2.1 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

μH

mH H

C pF nF

μF

R/|Z|

Ω

kΩ MΩ

Table 4-1 Units

|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 and 1 kHz.

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3. Range Setup:
RANGE and AUTO keys are used to set the measurement

range. AUTO key toggles ranging mode between “Auto”

and “Hold”. RANGE 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.

Range

Resistor

Range

Up

Range

Down

0

100kΩ

1

10kΩ

2

1kΩ

3

100Ω

4

20Ω

Ï

20kΩ

Ï

2kΩ

Ï

200Ω

Ï

20Ω

Ï

Ð

18kΩ

Ð

1.8kΩ

Ð

180Ω

Ð

18Ω

Ð

Table 4-2 Ranges

TH2821B OPERATION MANUAL

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* Note：

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

Ω≈

××××

=≈

+=

−

9.757

1021010001416.32

1

2

1

2

1

9

X

X

X

XX

fC

Z

fCj

RZ

π

π

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.

5. Correction Function

z Press CLEAR key to select the second function,

“SHIFT” will be lighted on the screen.

z Press CLEAR key to enter the correction function, the

following information will be displayed on the screen.

Figure 4-2 Correction Display

z Clear (Clear) is displayed in the primary parameter

display area, OpeN (OPEN), Short (Short) or Quit

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(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 according to the impedance
value of the device under test.

z Press any key to cancel the correction operation and

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

z When correction measurement is finished, PASS or FAIL

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

Figure 4-3 Open correction Passed

* 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 fixture, test leads and
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 (FAIL) will be displayed in

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

TH2821B OPERATION MANUAL

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reliably and perform the short correction again.

4． Th2821B 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 the 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.

6. Equivalent Circuit

Press EQU key to select the Series or Parallel circuit
mode.

* 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． TH2821B 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).

Capacitance Cp: from parallel to series

Circuit Mode：

Cp

Rp

Dissipation：

QRfC

D

PP

1

2

1

==

π

Series：

)1(

)1(

22

2

DDRR

CDC

PS

PS

+=

+=

TH2821B OPERATION MANUAL

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Capacitance Cs：from series to parallel

Circuit Mode：

Cs

Rs

Dissipation:

Q

CfRD

SS

1

2 ==

π

Parallel:

22

2

)1(

)1(1

DDRR

CDC

SP

SP

+=

+=

Inductance Lp：from parallel to series

Circuit Mode：

Lp

Rp

Dissipation:

QR

fL

D

P

P

1

2

==

π

Series:

)1(

)1(1

22

2

DDRR

LDL

PS

PS

+=

+=

Inductance Ls：from series to parallel

Circuit Mode：

Lp Rp

Dissipation：

QfL

R

D

S

S

1

2

==

π

Par allel:

22

2

)1(

)1(

DDRR

LDL

SP

SP

+=

+=

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

TH2821B OPERATION MANUAL

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

between series and parallel is determined by D

2

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, b ut
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%.

3.3 Battery Replacement

*Note：

The instrument will not be started, when the battery is weakening.
Replace the battery immediately.

z Loosen the three screws with suitable driver and

remove the bottom cover.

z Replace the degraded battery with a new DC 9V

battery.

z Model 1604, 006P or other equivalent battery must be

TH2821B OPERATION MANUAL

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used. Alkaline battery is recommended.

z If the instrument is not in use for more than three

months, if the external DC adapter is always be used,
please take out the battery.

z Close the bottom cover. The degraded battery must be

disposed of properly.

3.4 Clearing Instruction

To clean the instrument, use a soft cloth slightl y 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.

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Appendix

Message Code Table：

clea

Clear: Correction

OpeN

Open: Open correction

shor

Short: Short correction

P1~

P1—: High limit of P1 Bin

P1_

P1_: Low limit of P1 Bin

Mg

NG: No-Good

Q_

Q_: Low limit of quality factor

D~

D_: High limit of dissipation factor

Std

Std: Standard value (Nominal value)

ApO

APO: Auto Power Off

Cal

CAL: Accuracy Calibration

Psd

PSD: Password

Aler

Alert

OM

ON

Off

OFF

pass

Pass

faIl

Fail

Quit

Quit

First Edition2006-2