GW Instek GCP-300 User manual

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200ADC/140ARMS
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INSTRUCTION MANUAL
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200 Amp AC/DC Current Probe
GCP-300
DC‐300kHz

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TABLEOFCONTENTS
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General Safety Instructions...........................................................3
Safety Terms and Symbols............................................................4
Getting Started ...............................................................................5
Basic Operation..............................................................................7
Maintenance ......................................……………………………..…9
Specifications...............................................................................12
Replaceable Parts ........................................................................17
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General Safety Instructions:
Read the following safety instructions to avoid injury and prevent damage
to this product or any products connected to it. Use this product only as
specified.
Only qualified personnel should perform service procedures.
ToAvoidFireorPersonalInjury
ConnectandDisconnectProperly.Connect the probe output to the
measurement instrument before connecting the probe to the circuit under
test. Disconnect the probe input and the probe ground from the circuit under
test before disconnecting the probe from the measurement instrument.
ObserveAllTerminalRatings.To avoid fire or shock hazard, observe
all rating and markings on the product. Consult the instruction manual for
further ratings information before making connections to the product.
ReplaceBatteriesProperly.Replace batteries only with the proper type
and rating specified.
DoNotOperateWithoutCovers.Do not operate this product without
the covers or panels.
AvoidExposedCircuitry. Do not touch exposed connections and
components when power is present.
DoNotOperateWithSuspectedFailures.If you suspect there is
damage to this product, have it inspected by qualified service personnel.
DoNotOperateinWet/DampConditions.
DoNotOperateinanExplosiveAtmosphere.
KeepProductSurfacesCleanandDry.
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Safety Terms and Symbols:
Terms in This Manual. These terms may appear in this manual:
WARNING. Warning statements identify conditions or practices
that could result in injury or loss of life.
CAUTION. Caution statements identify conditions or practices
that could result in damage to this product or other property.
Terms on the Product. These terms may appear on the product:
DANGER indicates an injury hazard immediately accessible as you read
the marking.
WARNING indicates an injury hazard not immediately accessible as you
read the marking.
CAUTION indicates a hazard to property including the product.
Symbols on the Product. These symbols may appear on the product:
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Attention refer to operation Instructions.
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This instrument has double insulation.
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Getting Started:
The GCP-300 current probe enables a general purpose oscilloscope to
display AC and DC current signals up to 200 amps Peak(140A RMS). The
GCP-300 current probe can also make AC and DC measurements with a
multimeter by using the BNC-to-banana plug adapter.
Figure 1: shows the controls and indicators on the GCP-300 current probe.
Press Button
Battery Inside
(suggested outdoor using)
Max. 11Wire
DC Zero Offset
A
C Ada
p
tor In
p
ut
Range Selection
(Power On/Off)
Output into the BNC-to-
BNC coaxial cable

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Table 1: GCP-300 controls and indicators
Control/Indicator Description
Current flow symbol. The arrow shows the probe’s
polarity convention for measuring current flowing
from positive to negative.
Zero adjustment. Rotate to adjust the probe output
to zero when there is no current present. It may also
be used to offset a DC signal component. Zeroing is
not needed for AC measurements unless your
instrument cannot isolate a DC component (if
present).
OFF/Range switch. Slide the switch from OFF to
either the 10 mV/A or 100mV/A range. When either
range is selected, the probe is turned on, and the
green battery indicator lights. If the indicator does
not light, see Battery Notes and Battery Installation
on page11.
Battery indicator. The green battery indicator lights
when the probe is turned on. For more information,
see Battery Notes and Battery Installation on
page11.
Overload indicator. The red overload indicator
lights if the measured signal is greater than the
selected range capacity. Switch the probe to 10
mV/A if possible, or remove the probe from the
circuit.
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Basic Operation:
Before using the probe, the batteries or specified power adaptor must be
installed. See the battery installation instructions on page11.
WARNING!
Do not clamp the probe onto circuits with voltages greater than 600
VAC. Personal injury or damage to the probe may result.
Always connect the GCP-300 current probe output to the instrument
before clamping onto the circuit under test.
1. First connect the current probe BNC connector to double BNC connection
cable then connect to oscilloscope input. Start by setting the oscilloscope
voltage input channel to DC volts, and the voltage sensitivity scale to 0.1
V/div.
2. Move the OFF/ Range switch to the 10 mV/A or 100 mV/A position to turn
on the probe.
(※The GCP-300 current probe has a green LED power/battery indicator.
If the LED does not light, replace the battery or use specified power
adaptor.)
3. Use the ZERO adjustment to zero or offset the probe output detection of
residual magnetic DC charges.
4. Connect the probe to the
circuit by opening the jaws
and clamping around the
conductor. See Figure 2.
NOTE:
Clamping around both
the “hot” and neutral
wires may give you a
zero reading.
(Remember to unclamp
the probe from the
conductor before
disconnecting it from
your meter or
instrument).
Figure 2. Connecting the GCP-300 current probe.

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5. Adjust the probe channel and oscilloscope’s time base as necessary to
get a clear and stable view of the signal. Set the oscilloscope input to DC
volts to see both the AC and DC currents; set the channel to AC to see
the AC current only.
The current drawn by different devices look much different than that of
others. While the RMS current can only be used in low frequency current,
the momentary peaks may be quite high. Figure 3 shows the difference
between the line current drawn by a resistive load and a motor controller.
Figure 3. Typical current waveforms
Congratulations on your purchase of the GCP-300, a multifunctional
current probe. When connecting to a digital meter, use the BNC-to-
banana adapter. Connect the black lead to the meter COM (black letters
on the meter), and the red lead to the Vinput (red letters on the meter).
To measure only AC current, set the meter to measure AC volts.
To measure DC current, set the meter to measure DC volts. Note the
current convention arrow on the probe to get the proper polarity reading.
To increase the measurement sensitivity of the GCP-300 current probe,
loop additional turns of the wire under test through the jaws. See Figure
4. The sensitivity of the GCP-300 current probe is multiplied times the
number of loops in the jaws. For example: 10 mV/A X 4 turns = 40 mV/A.

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Figure 4: Increasing the sensitivity
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Maintenance:
Use the information in this section to properly maintain the operation of
your GCP-300 AC/DC Current Probe.
1. Notes on Battery and Power Converter:
The GCP-300 current probe uses a single square 9 V battery. This machine
is a high power product. Please use the specified alkaline battery.
As the battery in the GCP-300 current probe is drained, significant gain
errors may occur. The green LED will continue to light until a low battery
voltage of 6.5 V is reached.
If probe gain errors are detected, replace the battery with a fresh one.
As an alternative, an AC power converter can be used to avoid gain error
due to poor battery durability. Switch to a square 9V battery only when there
is no AC power supply available outdoors.
When using an AC power converter for an extended time, we suggest you
remove the battery from the compartment. This is because heating will
result in battery leakage, and battery electrolyte will rust the circuit board,
thus creating major damage. Furthermore, batteries are high pollution
products and therefore by reducing their usage, we will in turn protect the
environment.
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GCP-300 has in its design a priority external power circuit therefore it is safe
to simultaneously install the battery and the external power supply. During
usage, removing the external power supply will not produce waveform
anomaly or any damage. However when external power is used for an
extended time (more than 1 week), removal of battery is recommended.
This will avoid leakage of battery since the quality of the batteries is
something that is out of our control.
2. Battery Installation:
(1) Remove the probe from the circuit.
(2) Please push and open battery lid slightly from back of probe.
(3) While observing polarity, attach the new alkaline battery to the battery
connector buttons and place the battery in the specified area.
(4) Please close battery lid properly.
Figure 5. GCP-300 Battery Installation
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3. Cleaning:
To clean the probe exterior, use a soft cloth dampened in a solution of mild
detergent and water. To clean the core, open the jaw and clean the exposed
core surfaces with a cotton swap dampened with isopropyl alcohol
(isopropanol). Lubricate the jaws mating surfaces with light oil.
Do not clean with solvents or abrasives. Do not immerse the probe.
4. Preparation for Shipment:
Our company has designed a special box to be used for GCP-300,
convenient for storage and shipment. Please do not discard it.
If the original packaging is unfit for use or not available, use the following
packaging guidelines:
(1) Use a sturdy shipping carton having inside dimensions at least one inch
greater than the probe dimensions.
(2) Put the probe into a plastic bag or wrap to protect it from dampness.
(3) Place the probe into the box and stabilize it with light packaging material.
(4) Seal the carton with shipping tape.
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Specifications:
These characteristics apply to an adjusted GCP-300 AC/DC Current Probe
installed on an oscilloscope of any brand. The oscilloscope must be warmed
up for at least 20 minutes and be in an environment with the temperature at
10°C ~30°C and the humidity at 0~80%.
Table 2: Electrical Characteristics 
Current Ranges 10/100 mV/A
DC Accuracy, typical ±3% ±50 mA at 100 mV/A
(50 mA to 20 A peak range)
±4% ±50 mA at 10 mV/A
(500 mA to 80 A peak range)
±15% max at 10 mV/A
(80 A peak to 200 A peak range)
Gain versus frequency, typical See Figure 6
Maximum Working Current See Table 3
Maximum Working Voltage See Table 3
Maximum Float Voltage See Table 3
Frequency Range DC to 300 KHz (-3 dB)
Rise Time 1.2 us(Typ.)
Load Impedance: 1M, < 100pF
Battery Type and Life, typical 9V NEDA 1604A, IEC 6LR61
10 hours minimum (1 each)
DC signal linearity, typical See Figure 8
Phase shift, typical See Figure 9
NOTE:ThisclampadaptstoallmeasurementinstrumentswhichhaveaBNCinputandan
impedanceof1MΩ,<100pF.

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Table 3: Voltage and current ratings
Rating
Maximum working
current (A)
Maximum
Working
voltage (V)
Maximum
floating
voltage (V)
Range
10 mV/A
Range
100 mV/A
DC 200* 20 600 600
DC + peak
AC
200* 20 600 600
AC peak 200 20 600 600
AC peak-
peak 400 40 1200 -
RMS CAT III 140 14 300 300
RMS CAT II 140 14 600 600
RMS CAT I 140 14 600 600
*See Figure 7 for frequency derating.
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Table 4: Physical Characteristics
Dimensions 280 mm x 70mm x 32 mm
(11 x 2.8 x 1.3 inch)
Maximum Conductor Size 11 mm (0.43 inch)
Cable Length 100 cm( 3.3 feet)
Weight 260 g (9.5 oz) (without battery)
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Table 5: Environmental Characteristics
Temperature
Working
Storage
0°C to +50°C
(+32°F to +122°F)
-20°C to +80°C
(-4°F to +176°F)
Humidity 0°C to 40°C, 95% humidity
40°C to 50°C, 45% humidity
Pollution Degree 2
Figure 6. Gain versus frequency at 1 A peak, typical
100 1k 10k 30k 100k 300k 1M
100 mV/A range
10 mV/A range
-1
-2
-3
-4
-5
0

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Figure 7: Maximum current versus frequency
Figure 8: DC signal linearity in the 10 mV/A range, typical
10 100 1k 10k 100k 300k 1M
450A
0A
100A
150A
200A
250A
300A
350A
400A
315A
0A
70A
105A
140A
175A
210A
245A
280A

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Table 6: Certifications and compliances
EC Declaration
of Conformity
Compliance was demonstrated to the following
specification as listed in the Official Journal of the
European Union:
Low Voltage Directive 2014/35/EU
EN 61010-1: 2010 (Third Edition)
EN 61010-2-032: 2012 (Third Edition)
-Low Voltage
Directive
EN 61010-2-033: 2012 (First Edition)
Figure 9:
Phase versus
frequency at 1 A
peak, typical
100 1k 10k 100k 300k
-150
-100
-50
-10
0
100 mV/A range
10 mV/A range
-EMC Directive EMC Directive 2014/30/EU
EN 61326-1: 2013
EN 61326-2-1: 2013
EN 61326-2-2: 2013
CISPR 11: 2009+1: 2010
EN 61010-3-2: 2014
EN 61010-3-3: 2013

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Replaceable Parts:
The GCP-300 AC/DC Current Probe is shipped with the following
items:
One instruction manual (English version).
One BNC TO BNC Coaxial Cable Line, length 100cm
One AC power converter (AC voltage depending on region)
Recommended accessory for use with digital meter:
One BNC to banana plug adapter, designed with color fool proof design to
avoid polarity mistake when connecting to digital meter.
The GCP-300 does not have any user repairable assemblies. If you
should have trouble with your probe, contact your local Service Center or
representative for help.
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