Center 28 Manual

Also See for 28:

Instruction manual (14 pages)

Table of Contents

Contents

1 GENERAL SPECIFICATION
2 ELECTRICAL SPECIFICATION
3 DESCRIPTION OF THE INSTRUMENT
- 3.1 Description Of The Display
- 3.2 Description Of Front And Rear
4 BUTTON INSTRUCTION
- 4.1 HOLD Function
- 4.2 PEAK Function
5 MEASURING INSTRUCTION
6 BATTERY CHANGING
7 MAINTENANCE
- 7.1 REMARK
- 7.2 CLEANING
8 SAFETY INFORMATION
- 8.1 Environmental Conditions
- 8.2 Explanation Symbols
9 Documents / Resources
- 9.1 References
- 9.2 Download manual

Center 28 Manual

GENERAL SPECIFICATION

Digital Display:
4 digital liquid crystal (LCD), Maximum reading 6000.

Polarity:
When a negative signal is applied, the signal appears.

Low Battery Indication:
When the battery is under the proper operation range, will appear on the LCD display.

Sample Rate:
2 times/sec.

Power Source:
CR2032 (3VDC) X 1
Typical battery Life: 24 hours (without buzzer)

Auto Power Off:
If there is no key or dial operation for 10 minutes, the meter will power itself off to save battery consumption. This function can be disabled by press and hold the "HOLD " button then power the unit on.

Over Load:
When the signal larger than the maximum will be show .

Maximum jaw opening:
40 mm

Dimensions:
207 x 66 x 26 mm

Weight:
Approx.153g (with battery)

Accessories:
Carrying case, Battery, Test Lead & Instruction Manual.

ELECTRICAL SPECIFICATION

The accuracy specification is defined as ±[...%reading+...count ] at 23±5°C, ≦ 80 %RH. True RMS for VAC and AAC accuracy are specified from 5% to 100% of range, crest factor CF <1.6 at full scale & CF < 3.2 at half scale.

Direct Voltage

( )

Range	Resolution	Accuracy	Overload Protection
6V	0.001V	±1% ± 2dgts	600Vrms
60V	0.01V
600V	0.1V

Input impedance: 10 MΩ

Direct Voltage (Peak Model)

Range	Resolution	Accuracy	Overload Protection
600V	0.1V	±2% ± 3dgts	600Vrms

warning Note: minimum DC voltage measurement range: 1Vrms

Alternating Voltage

( )

Range	Resolution	Accuracy	Overload Protection
6V	0.001V	±1.2%±5dgts (50~500Hz)	600Vrms
60V	0.01V
600V	0.01V

LCD displays 0 when the reading < 20counts (6V range only)
Input impedance: 10 MΩ

Alternating Voltage (Peak Model)

Range	Resolution	Accuracy	Overload Protection
600V	0.1V	±2.4%±5dgts	600Vrms

warning Note: minimum AC voltage measurement range: 1Vrms

Alternating Current

( )

Range	Resolution	Accuracy	Overload Protection
600A	0.1A	1.9%±5dgts(50~60Hz) 2.5%±5dgts(45~500Hz)	1000Arms
1000A	1A	1.9%±5dgts(50~60Hz) 2.5%±5dgts(45~500Hz)	1000Arms

Alternating Current (Peak Model)

Range	Resolution	Accuracy	Overload Protection
1000A	1 A	±2.9% ± 5dgts	1000Arms

Resistance

()

Range	Resolution	Accuracy	Overload Protection
600Ω	0.1Ω	±1% ± 2dgts	600Vrms
6KΩ	0.001KΩ
60KΩ	0.01KΩ
600KΩ	0.1KΩ

Continuity

Range	Resolution	Accuracy	Overload Protection
600Ω	0.1Ω	±1% ± 2dgts	600Vrms
	Ohm function Buzzer<100Ω

Capacitance Measurement

()

Range	Resolution	Accuracy	Overload Protection
6 μF	0.001 μF	±3% ± 10dgts	600Vrms
60 μF	0.01 μF
600 μF	0.1 μF

warning Note: minimum CAP measurement range > 0.01 μF

Frequency (Hz) & Duty Cycle (%)

Frequency (Hz) ) (Autorange)

Function	Range	Resolution	Accuracy	Sensitivity	Overload Protection
Current Frequency	600Hz	0.1Hz	±0.2% ±2dgts (30~6KHz)	3Arms	1000Arms
	6KHz	0.001KHz
Voltage Frequency	600Hz	0.1 Hz	±0.2% ±2dgts (10~60KHz)	5Vrms	600Vrms
	6KHz	0.001KHz
	60KHz	0.01KHz

Input impedance: 700 kΩ

Duty Cycle (%)(Voltage)

Range	Resolution	Accuracy	Sensitivity	Overload Protection
1~99% (1-500Hz)	0.1%	±0.5% duty	5Vpp	600Vrms
2~98% (500~1KHz)

DESCRIPTION OF THE INSTRUMENT

Description Of The Display

	Auto Power Off Indication
	Polarity Indication
	Low Battery Indication
	Alternative Source Indication
	Direct Source Indication
	Current Measurement Indication
	Voltage Measurement Indication
	Capacitance Measurement Indication
	Data Hold Indication
	Peak Data Indication
	Continuity Test Indication
/M/K	Measurement Unit
	Resistance Measurement Indication
	Frequency Measurement Indication
	Duty Cycle Measurement Indication
	Danger Voltage Indication

Description Of Front And Rear

Current Sensing Clamp
Safety Protection Ring
Clamp Opening Handle
Function Select Dial
LCD Display
AC/DC Voltage & /Ω & Hz/% Select Button
Peak Hold Button
Data Hold Button
COM Input Terminal
Positive Input Terminal
Battery Cabinet

BUTTON INSTRUCTION

HOLD Function

It is possible to freeze the value displayed by pressing on the "HOLD" button. To deactivate this function, press the "HOLD" button a second time.

PEAK Function

If you press on the "PEAK" button, the display will show " " symbol. When there is a value input that value will be indicated frozen in the display. If a bigger peak value is input, the peak value will be updataed and indicated frozen in the display. When you press on the button again, the function will return to the normal mode.

AC/DC Voltage Select and Select and Hz/% Select Button

Press button to select function.
To select function AC or DC in Voltage range.
To select continuity or Resistance in range.
To select function frequency(Hz) or Duty Cycle(%) measurement in Hz range.

MEASURING INSTRUCTION

AC Voltage Measurement

Switch the main function selector to range.
Connect red test lead to"+"terminal and black one to the "COM" terminal.
Measure the voltage by touch the test lead tips to the test circuit where the value of voltage is needed.
Read the result from the LCD panel.

DC Voltage Measurement

Switch the main function selector to range.
Connect red test lead to "+" terminal and black one to the "COM" terminal.
Measure the voltage by touch the test lead tips to the test circuit where the value of voltage is needed.
Read the result from the LCD panel.
DC Voltage Measurement

warning Note: When the reading is exceeding 30V in ACV or DCV, the symbol will be displayed on.

AC Current Measurement

Switch the main function selector to range.
Open the clamp by pressing the jaw-opening handle and insert the cable to be measured into the jaw.
Close the clamp and get the reading from the LCD panel.

Note:
Before this measurement, disconnect the test lead with the meter for safety.
In some occasion that the reading is hard to read, push the HOLD button and read the result later.
AC Current Measurement

Resistance Measurement

Switch the main function to range. Connect red test lead to "+"terminal and black one to the"COM"minal.
Connect tip of the test leads to the points where the value of the resistance is needed.
Read the result from the LCD panel.

warning Note:
When take resistance value from a circuit system, make sure the power is cut off and all capacitors need to be discharged.

Continuity Test With Buzzer

Switch the main function to range.
Connect red test lead to"+"terminal and black one to the "COM" terminal.
Connect tip of the test leads to the points where the conduction condition needed.
If the resistance is under 100Ω, the beeper will sound continuously.
Continuity Test With Buzzer

Capacitance Measurement

Switch the main function selector to range. Connect red test lead to "+" terminal and black one to the "COM" terminal.
Connect tips of the test leads to the capacitor being tested.
Read the capacitance value on LCD.

warning Note:
To avoid damage to the meter, disconnect circuit power and discharge all capacitors before measuring capacitance. Use the DC voltage function to confirm that the capacitor is discharged.

Measurement Of The Voltage Frequency

Switch the main function to range. Connect red test lead to"+"terminal and black one to the "COM"terminal.
Place the touch prods in contact with the points whose frequency is to be measured.
Read the result on the LCD panel.

Measurement Of The Current Frequency

Switch the main function to range.
Open the clamp by pressing the trigger. Encircle the conductor and close the jaws correctly by releasing the trigger.
Read the result on the LCD panel.

Measurement Of Duty Cycle (%)

Switch the main function to range.
Press button to % range.
Connect red test lead to"+"terminal and black one to the "COM" terminal.
Place the touch prods in contact with the points whose % is to be measured.
Read the result on the LCD panel.
A duty cycle is the percent of time that an entity spends in an active state as a function of the total time under consideration.

Definition
In a periodic event, duty cycle is the ratio of the duration of the event to the total period of a signal.

duty cycle

where
𝒯 is the duration that the function is active.
T is the period of the function.

BATTERY CHANGING

When the battery voltage drop below proper operation range the symbol will appear on the LCD display and the battery needs to be changed.
Before changing the battery, switch the main dial to "OFF "and disconnect test leads.
Open the back cover by an appropriate tool.
Replace the old battery with new 3V (CR2032) battery.
Close the Battery cover.

MAINTENANCE

Before open the meter, disconnect both test lead and never uses the meter before the cover is closed.

To avoid contamination or static damage, do not touch the circuit board without proper static protection.

REMARK

If the meter is not going to be used for a long time, take out the battery and do not store the meter in high temperature or high humidity environment.
When take current measurement, keep the cable at the center of the clamp will get more accurate test result.
Repairs or servicing not covered in this manual should be performed only by qualified personal.

CLEANING

Periodically wipe the case with a dry cloth.
Do not use abrasives or solvents on these instruments.

SAFETY INFORMATION

Do not operate the tester if the body of meter or the test lead look broken.
Check the main function dial and make sure it is at the correct position before each measurement.
Do not perform resistance and continuity test on a live power system. Do not apply voltage between the test terminals and test terminal to ground that exceed the maximum limit record in this manual.
Keep the fingers after the protection ring when measuring through the test lead.
Chang the battery when the symbol appears to avoid incorrect data.