Introduction
Specifications
User’s Guide Model CA250
400A AC/DC Current Clamp-on MultiMeter Adaptor
Current Measurements
NOTE: This device has a 30-minute automatic shut-off feature
Congratulations on your purchase of the Extech CA250 400 Amp AC/DC
Clamp-On MultiMeter Adaptor. With this clamp adaptor, a current can be measured by simply clamping around a single conductor. The adaptor outputs an mV signal that is proportional to the measured current and displayed on a DMM. Careful use of this device will provide years of reliable service.
mV when measuring DC amps or to the lowest voltage range.
2. Connect the RED test lead to the DMM '+' Voltage terminal and the BLACK lead to the '-' COM terminal.
3. Set the adaptor to the 40A (AC or DC) or the 400A (AC or DC) range.
4. Press the Jaw Trigger to open the jaw and clamp around a single conductor.
5. The unit will output an AC or DC voltage proportional to the measured current. (40A range:10mV/A, 400A range:1mV/A)
6. Read the voltage on the DMM display and interpret as current.(direct mV to A on the 400A range, divide by 10 on the
40A range)
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2. Set to AC or DC mV 2
Measurement Ranges 0 to 40 Amps AC/DC
0 to 400 Amps AC/DC
Adaptor Output 10mV/Amp on the 0 to 40A range
1mV/Amp on the 0 to 400A range
Frequency range 50/60Hz
Safety
Standards
Accuracy
EN61010-1 and IEC61010-1 2nd Edition (2001) to Category III 600V and Category IV 300V;
Pollution Degree 2 in accordance with IEC 664 indoor use.
CC
0 to 40A ± (2.5% + 0.1A)
0 to 400A ± (2.8% + 0.5A)
Jaw size
Storage Conditions
30mm (1.2")
Operating Conditions 0 to 50 o C (32 to 122 o F) < 70% RH
-20 to 70 o C (-4 to 158 o F) < 80% RH
Battery
Dimensions/Weight
2 – 1.5V “AAA”
146 x 60 x 32mm (5.8 x 2.3 x 1.3");
226g (8oz)
Safety
Safety Symbols
This symbol, adjacent to another symbol or terminal, indicates the user must refer to the manual for further information.
This symbol indicates that double insulation is used.
WARNING: This indicates that a potentially hazardous condition which, if not avoided, could result in death or serious injury.
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6. DC Zero adjust
DC Zero
A hysteresis voltage may appear when the clamp is set to the DC position. With no conductor in the jaw, adjust the DC Zero adjust until the DMM display indicates zero. If the voltage is beyond the range of the zero adjust, snap the jaw open and shut several times to clear the hysteresis. Set DMM to DC mV range.
Note: Verify the zero or re-zero the unit prior to all DC current measurements and range changes.
Note: DC current measurements are polarity sensitive. Reverse the conductor direction in the jaw to change the polarity.
Note: Do not apply voltage to the clamp adaptor’s test leads
Note: Clamp a single conductor only, do not clamp the hot and neutral simultaneously.
X
Note: The clamp jaws must be fully closed for proper measurements.
On large conductors or line splitters, make sure there is no gap between the upper and lower jaw.
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Safety Precautions
1. WARNING: Improper use of this meter can cause damage, shock, injury or death. Read and understand this manual before operating the meter.
2. Inspect the condition of the test leads and the meter itself for any damage before operating the meter. Repair or replace any damage before use.
3. Do not use on non-insulated conductors at voltages greater than
600VAC rms or DC.
You, as the end user, are legally bound (EU Battery
ordinance) to return all used batteries, disposal in the
household garbage is prohibited! You can hand over your used batteries / accumulators at collection points in your community or wherever batteries / accumulators are sold!
Disposal: Follow the valid legal stipulations in respect of the disposal of the device at the end of its lifecycle
Non-Contact AC Voltage Measurements
WARNING: Risk of Electrocution. Before use, always test the
Voltage Detector on a known live circuit to verify proper operation
1. Touch the probe tip to the hot conductor or hold next to the hot side of the electrical outlet.
2. If AC voltage is present, the detector LED will illuminate.
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All rights reserved including the right of reproduction in whole or in part in any form
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CA250-en-EU_V1.5 8/14
