GW Instek GCP-500 User manual

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150ADC/100ARMS
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INSTRUCTION MANUAL
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150 Amp AC/DC Current Probe
GCP-500
DC‐500kHz

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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-500 current probe enables a general purpose oscilloscope to
display AC and DC current signals up to 150 amps Peak (100A RMS). The
GCP-500 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-500 current probe.
Output into the BNC-to-
BNC coaxial cable
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)

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Table 1: GCP-500 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 20 mV/A or 200mV/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 20 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-500 current probe output to the instrument
before clamping onto the circuit under test.
1. First connect the current probe BNC connector to BP-250 (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 20 mV/A or 200 mV/A position to turn
on the probe.
(※The GCP-500 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-500, 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-500 current probe, loop
additional turns of the wire under test through the jaws. See Figure 4. The
sensitivity of the GCP-500 current probe is multiplied times the number of
loops in the jaws. For example: 200 mV/A X 4 turns = 800 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-500 AC/DC Current Probe.
1. Notes on Battery and Power Converter:
The GCP-500 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-500 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.