GTC CT8022 User manual

1. SAFETY RULES
•This meter is designed for indoor use at temperatures between 0°C to 40°C and
altitudes up to 2,000m.
•Toensurethatthemeterisusedsafely,followallsafetyandoperatinginstructionsin
thisoperationmanual.Ifthemeterisnotusedasdescribedinthisoperationmanual,
the safety features of this meter might be impaired.
•Do not use the meter if the meter or test leads look damaged ,or if you suspect that
the meter is not operating properly.
•Whenusingtheinstrument,keepyourfingersbehindthefingerguardsontheplastic
casing and probes.
•Disconnect the live test lead before disconnecting the common test lead.
•Makesurepowerisoffbeforecutting,desoldering,orbreakingthecircuitwires.Small
amounts of current can be dangerous.
•Do not apply more than 600 VDC or 600VAC rms between a terminal and ground.
•To avoid electrical shock, use CAUTION when working above 60V DC or 25V AC
rms. Such voltages pose a shock hazard.
•Never make measurements with the battery cover off.
•To avoid electrical shock or damage to the meter, do not exceed the input limits.
2. INTERNATIONAL SYMBOLS
Important information Dangerous Voltages
see manual Continuity
AC Ground
DC Double Insulation
3. TECHNICAL SPECIFICATIONS
3.1 General Specifications
Display: 3-3/4 digits LCD, max. of 3999 display
with
decimal point and engineering units
Polarity: Automatic, (-) negative polarity indication
Zero adjustment: Automatic
Sample rate: 0.5 Sec.
Over range indication: Reading “ ” is displayed
Power: 9-volt battery type NEDA 1604, IEC6F22
Battery life: Approx. 50 hours. (w/ alkaline batteries)
Dimension: 141 x 69 x 36 mm.
Weight: Approx. 160g (including battery).
Accesories: User’s Manual, Alligator Clip, Probes
Cups and 9V alkaline battery
3.2 Electrical Specifications
•The mark next to the probe tip, is a warning that the input
voltage should not exceed the indicated values. This is to pre-
vent personal injuries and damage to the internal circuitry.
•The function switches should be set to the function which you
want to test before operation.
•Accuracies are ±(% of reading + number of least significant
digits) at 23°C ±5°C, less than 75% RH.
4. OPERATION
4.1 Instrument Description
1) Case
2) 3-3/4 Digit LCD display
3) ON/OFF and Range switch
4) Function switch
5) Fixed test lead with probe
6) Fixed probe tip and fuse cap
7) Battery cover
8) Display hold push button (back of the unit)
9) Probes cups
10) Alligator clip
Function Range Accuracy Input
Impedance Remarks Overload Protection
DC Voltage 4000mV, 60V
600V 0.8%+1 10 M- 600 Vp-p
AC Voltage 4000mV, 60V
600V 1.2%+3 10 M40~400Hz 600 Vp-p
DC Current 40 - 400 mA 1.2%+3 - - 400 mA/
250V Fuse
AC Current 40 - 400 mA 1.2%+5 - 40~400Hz 400 mA/
250V Fuse
4.2 Display Description
4.3 Measurement Procedures
CAUTION: Maximum Input Voltage is 600Vrms,do not exceed
this rating to avoid personal injuries or damage to
the instrument. The range FUNCTION/RANGE
switch should be set to the range you want to test
before the operation.
CAUTION: Always ensure that the correct terminals are used for
the type of measurement to be made. Avoid making
connections to “live” circuits whenever possible.
When making current measurements ensure that
the circuit is not “live” before opening it in order to
connect the test leads.
Function Range Accuracy Input
Impedance Remarks Overload Protection
Resistance
400, 4k,
40k,400k
4M
1.0%+2 -
1.2 mA
max. test
current
250 Vp-p
40 M1.5%+2 -
0.47 mA
max. Test
current
250 Vp-p
Diode Test Test Current:1.0± 0.6mA Test Voltage: 3.2 V Max. 250 Vrms
Continuity Beeps when < 100Ω3VDC Max. Test Voltage 250 Vrms
Logic level Logic High > 2.0V Logic Low < 0.8V 250 Vrms
8.8.8.8
DH HI LO
MKΩ
mVA
Replace battery
Data hold
TTL logic status
Continuity
beeper enable
Measurement units
Digital reading
AC
Neg. polarity
DC
1
234
8
6
9
10
57
8.8.8.8
DH HI LO
MK:
mVA
CT8022

4.3.1 DC Voltage measurement
• Set the FUNCTION SWITCH to “V” and the RANGE SWITCH to
“DC/ ” function.
• Connect the test leads across the source or load under
measurement.
• The measurement and polarity will be shown the LCD Display
when the probes are connected.
4.3.2 AC Voltage measurement
• Set the FUNCTION SWITCH to “V” and the RANGE SWITCH to
“AC/ ” function.
• Connect the test leads across the source or load under
measurement.
• The measurement will be shown on the LCD Display when the
probes are connected and current flows through the meter.
4.3.3 DC Current measurement
• Set the FUNCTION SWITCH to “A” and the RANGE SWITCH to
“DC/ ” function.
• Connect the test leads in series with the source or circuit under
measurement.
• The measurement and polarity will be shown the LCD Display
when the probes are connected and current flows through the
meter.
4.3.4 AC Current measurement
• Set the FUNCTION SWITCH to “A” and the RANGE SWITCH to
“AC/ ” function.
• Connect the test leads in series with the source or load under
measurement.
• The measurement will be shown on the LCD Display when the
probes are connected and current flows through the meter.
4.3.5 Resistance measurement
CAUTION: Maximum Input Voltage for this function is 250
Vrms for less than 10 Sec., do not exceed this
rating to avoid personal injuries or damage to the
instrument. Also ensure there is no power applied
to the component or circuit and all capacitors are
discharged.
• Set the FUNCTION SWITCH to “R” and the RANGE SWITCH to
“DC/ ” function.
• Connect the test leads across the component or circuit under
measurement.
• The range will adjust automatically for optimal readout, and the
measurement will be shown the LCD Display when the probe are
connected.
4.4 Other Functions
CAUTION: Maximum Input Voltage for this function is 250
Vrms for less than 10 Sec., do not exceed this
rating to avoid personal injuries or damage to the
instrument. Also ensure there is no power applied
to the diode.
4.4.1 Continuity Test
• Set the FUNCTION SWITCH to “R” and the RANGE SWITCH to
“AC/ ” function.
• Connect the test leads across the circuit or component to test.
• Buzzer will sound if the circuit resistance is below 100.
4.4.2 Logic Level Test
• Set the FUNCTION SWITCH to “TTL” and the RANGE SWITCH
to “DC/ ” function.
• Connect the test leads across the source or circuit under test.
• The logic level will be shown as “HI” or “LO” on the LCD display
according to the table below:
© Copyright 2017 General Technologies
* The display will switch between HI and LO, but the response is
affected by the pulses frequency
4.4.3 Display Hold
A push button switch at the back of the unit is used to hold display
readings during measurements.
• Pressing the button holds the display reading, and “DH” appears
on the display.
• Pressing the button again resumes normal operation.
4.4.4 Auto Power OFF
The meter will turn off automatically to extend the battery life after
approx. 30 minutes without operating. To turn it on again, set
the FUNCTION SWITCH to the “OFF” position and then to the
desired range position.
5. MAINTENANCE
CAUTION: Before attempting battery removal or replacement,
disconnect test leads and remove the instrument
from any energized circuit to avoid shock hazard.
5.1 Battery Replacement
• When the battery needs replacement, the battery symbol will
appear in the lower left hand side of the LCD display.
• To replace the battery, remove the screw at the back Battery
Cover and replace with a new 9 V alkaline battery type NEDA
1604 or IEC6F22, observing the polarity as indicated at the back
of the case.
• Reinstall the battery cover and tighten the securing screw.
5.2 Fuse replacement
• To replace the internal fuse, turn the Fuse Cap counter clockwise,
to release the Fuse Cap assembly.
• Take out the blown fuse and replace with a type IEC60127-2 or
UL248-14 (5 x 20mm) fast acting fuse, rated at 400mA/250V.
• Replace the fuse cap, by inserting it in the meter body and turning
the Fuse Cap assembly clockwise, unitl it locks.
5.3 Cleaning
Periodically wipe the case with a soft damp cloth and mild household
cleanser. Do not use abrasives or solvents. Ensure that no water gets
inside the instrument to prevent possible shorts and damage.
6. WARRANTY
One year limited warranty, excluding batteries and fuses. For details
see Standard Warranty Information in our webpage or you may request
a printed copy.
Input Voltage TTL Logic Status Display
Above 2.0 V High HI
Below 0.8 V Low LO
0.8 to 2.0 V Undertermined -
Negative input (-V) Undertermined HI/LO or LO/HI*
Pulse Undertermined HI/LO or LO/HI*
General Technologies Corp.
#121 - 7350 72nd Street Tel.: [phone]
Delta, BC V4G 1H9 Fax: [phone]
Canada www.gtc.ca