GW Instek GCP-1000 User manual

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DC‐1MHz
(1mV=2mAat500mV/A)
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INSTRUCTION MANUAL
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GCP-1000
70 Amp AC/DC Current Probe

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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-1000 current probe enables a general purpose oscilloscope to
display AC and DC current signals up to 70 amps Peak (50A RMS). The
GCP-1000 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-1000 current probe.
Output into the BNC-to-
BNC coaxial cable
Press Button
Battery Inside
(suggested outdoor using)
Max. 10.3Wire
DC Zero Offset
A
C Ada
p
tor In
p
ut
Range Selection
(Power On/Off)

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Table 1: GCP-1000 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 50 mV/A or 500mV/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 50 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-1000 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 50 mV/A or 500 mV/A position to turn
on the probe.
(※The GCP-1000 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-1000 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-1000, 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-1000 current probe,
loop additional turns of the wire under test through the jaws. See Figure 4.
The sensitivity of the GCP-1000 current probe is multiplied times the
number of loops in the jaws. For example: 500 mV/A X 4 turns = 2000 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-1000 AC/DC Current Probe.
1. Notes on Battery and Power Converter:
The GCP-1000 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-1000 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-1000 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-1000 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-1000,
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-1000 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 50/500 mV/A
DC Accuracy, typical ±3% ±20 mA at 500 mV/A
(20 mA to 7A peak range)
±4% ±200 mA at 50 mV/A
(200 mA to 50 A peak range)
±15% max at 50 mV/A
(50 A peak to 70 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 1MHz (-3 dB)
Rise Time 0.35 us(Typ.)
Load Impedance: 1M, < 100pF
Battery Type and Life, typical 9V NEDA 1604A, IEC 6LR61
8 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
50 mV/A
Range
500 mV/A
DC 70*7 600 600
DC + peak
AC
70*7 600 600
AC peak 70 7 600 600
AC peak-
peak
140 14 1200 -
RMS CAT III 50 5 600 600
RMS CAT II 50 5 600 600
RMS CAT I 50 5 600 600
*See Figure 7 for frequency derating.
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Table 4: Physical Characteristics
Dimensions 262 mm x 81mm x 36 mm
(10.3 x 3.2 x 1.4 inch)
Maximum Conductor Size 10.3 mm (0.4 inch)
Cable Length 100 cm( 3.3 feet)
Weight 310 g (11 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
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Figure 6. Gain versus frequency at 1 A peak, typical
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-1
-2
-3
-4
-5
0
500 mV/A range
50 mV/A range
100 1k 5k 10k 50k 100k 500k 1M 3M

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Figure 7. Maximum current versus frequency
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Figure 8. DC signal linearity in the 50 mV/A range, typical
100 1k 10k 100k 500k 1M
0A
7A
14A
21A
28A
35A
42A
49A
56A
10A
20A
30A
40A
50A
60A
80A
70A
0A

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Table 6: Certifications and compliances 
Figure 9.
Phase versus
frequency at 1 A
peak, typical
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)
-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
100 1k 10k 100k 500k 1M
500 mV/A range
50 mV/A range
-150
-100
-50
-10
0

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Replaceable Parts:
The GCP-1000 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-1000 does not have any user repairable assemblies. If you should
have trouble with your probe, contact your local Service Center or
representative for help.