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Extech / Insulation Tester

Extech MG325 CAT IV Insulation Tester/True RMS MultiMeter

Extech logo

2000 GOhm/1000V Insulation Tester/DMM with Datalogging

Combines a 200GΩ/1000V high range Insulation Tester with a full-featured True RMS MultiMeter in a single, compact instrument. CAT IV-600V safety rating ensures the highest level of protection.

CAT IV    CE    1 Year

PDF Logo    MG325 Datasheet
PDF Logo    MG325 Users Manual
SKU: Extech MG325 Categories: Extech, Insulation Tester Tags: EXTECH, Insulation Testers Brand: Extech
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  • Description
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The Extech MG325 features a rugged design for heavy duty use. The MG325 measures Insulation Resistance, AC/DC Voltage, Frequency, Leakage Current, Low Resistance, Continuity, and Capacitance. Insulation Resistance tests are automatic ranging with 5 test voltages from 50V to 1000V. The MG325 can store and recall up to 99 measurements. The Extech MG325 is suitable for measuring the insulation resistance.

Extech MG325 Features:

  • DC and True RMS AC Voltage Measurments to 600V
  • CAT IV-600V safety rating
  • Insulation Resistance Measurements up to 200G
  • Frequency of the AC Voltage
  • Leakage Current Insulation test mode
  • Capacitance Measurements
  • Low Resistance and Continuity Measurements with ZERO function
  • Auto Ranging measurments
  • Polarization Index (PI) and Dielectric Aborption Ratio (DAR) tests
  • Five (5) Insulation Resistance test voltages (50, 100, 250, 500, and 1000V)
  • Insulation Resistance tests in 10% voltage steps (from 50% to 120% of range)
  • Eight (8) Insulation Resistance measurement ranges (automatic ranging)
  •  Pass/Fail Comparator function for Insulation Resistance and Continuity
  • Auto-discharge at end of test
  • Output voltage alert light and display symbols
  • Hand’s free test lock feature Manually store and recall up to 99 readings
  • Overload indication
  • Remote test probe for controlling the TEST button remotely
  • Test leads, alligator clips, batteries, user manual, and case included
 Extech MG325 Specifications :    
Function Range Resolution Accuracy
DC Voltage ±600V 0.01V to 1V ±(2.0% reading + 3 digits)
AC Voltage 0~600V 0.01V to 1V ±(1.5% reading + 5 digits)
Specified from 5% of range to 100% of range
Input impedance: 10MΩ
Frequency 45~400Hz (unspecified for frequency >400Hz) Input protection: 600V DC and AC rms
Frequency 45~1kHz 0.1Hz ±(0.1% reading + 3 digits); 45~450Hz
Frequency measurements are shown for ACV tests in the auxiliary display area Measurements 450Hz~1kHz are for reference only; accuracy not specified
Continuity 0.01~100Ω
(@ 20mA test current)
0.01~0.1Ω ±(1.5% reading + 5 digits)
0.01~100Ω
(@ 200mA test current)
0.01~0.1V ±(1.5% reading + 4 digits)
Continuity threshold 30Ω (programmable ON/OFF continuity buzzer)
Open Circuit Voltage: 5V approximately
Resistance 0.001k~10MΩ 0.001kΩ.~ 0.1MΩ ±(3.0% reading + 3 digits)
Capacitance 0.1nF~500µF 0.1nF~0.1µF ±(5.0% reading + 5 digits)
Insulation Resistance Measurements
Test Voltage Range Min. Resolution Accuracy
50V 0.00M~0.99GΩ
1.00G~10.0GΩ
0.01MΩ ~ 0.01GΩ
0.01GΩ ~ 0.1GΩ
±(3% + 3 digits)
±(3% + 3 digits) reading; ±4%/GΩ
100V 0.00M~0.99GΩ
1.00G~20.0GΩ
0.01MΩ ~ 0.01GΩ
0.01GΩ ~ 0.1GΩ
±(3% + 3 digits)
±(3% + 3 digits) reading; ±2%/GΩ
250V 0.00M~0.99GΩ
1.00G~50GΩ
0.01MΩ ~ 0.01GΩ
0.01GΩ ~ 0.1GΩ
±(3% + 3 digits)
±(3% + 3 digits) reading; ±0.8%/GΩ
500V 0.00M~0.99GΩ
1.00G~100GΩ
0.01MΩ ~ 0.01GΩ
0.01GΩ ~ 0.1GΩ
±(3% + 3 digits)
±(3% + 3 digits) reading; ±0.4%/GΩ
1000V 0.00M~0.99GΩ
1.00G~200GΩ
0.01MΩ ~ 0.01GΩ
0.01GΩ ~ 0.1GΩ
±(3% + 3 digits)
±(3% + 3 digits) reading; ±0.2%/GΩ
Short-circuit current < 2mA
250V DC and AC rms input limit
Insulation Resistance Test Voltage Outputs
Output Voltage Test Steps (50~120%) Load Overload Test current Short-circuit current
50V (0%~+20%) (25~60V) 50kΩ 250VAC/DC 1mA ≤2mA
100V (0%~+20%) (50~120V) 100kΩ 250VAC/DC 1mA ≤2mA
250V (0%~+20%) (125~300V) 250kΩ 250VAC/DC 1mA ≤2mA
500V (0%~+20%) (250~600V) 500kΩ 250VAC/DC 1mA ≤2mA
1000V (0%~+20%) (500~1200V) 1MΩ 250VAC/DC 1mA ≤2mA
Operating range per EN61557: 0.10MΩ~1.00GΩ (output voltage >/= 50V) Short-circuit current: 2mA (0%~50%)
Leakage current accuracy: ± (10% + 3 digits)
Test voltage output step range is 50%~120% in 10% steps
Note: Accuracy is stated at 23°C (75°F) and 45~75% RH.
Note: Calibration interval: 1 year maximum
Note: Temperature coefficient: 0.1 x stated accuracy/°C
Note: Accuracy specifications consist of two elements:
· (% reading) This is the accuracy of the measurement circuit.
· (+ digits) This is the accuracy of the analog to digital converter.
General Specifications
Display                                      5999 count, backlit, LCD with bargraph
Ranging                                    Automatic
Storage capacity                      99 records (01-99)
Input Impedance                      >10MΩ
AC Response                           True rms
ACV Bandwidth                        45Hz to 400Hz
Over range indication              “>” is displayed in Insulation Resistance and Continuity modes
Auto Power Off                        After 10 minutes of inactivity
Polarity                                     Automatic (no indication for positive); Minus (-) sign for negative
Measurement Rate                   2 times per second, nominal
Low Battery Indication            “         ” is displayed if battery drops below operating voltage
Battery                                      Six (6) 1.5V ‘AA’ batteries
Consumption                           500mA (at a 1000V test voltage); 17mA in nominal conditions
Fuse                                          500mA/600V fast blow
Enclosure                                 Double molded, IP 40

 

Operating Temperature           0ºC~40ºC (32ºF~104ºF)

Storage Temperature              -20°C~60°C (-4°F~140°F)

Operating Humidity                 <85%

Storage Humidity                     <90%
Operating Altitude                   2000m (7000ft,) maximum
Weight                                       0.7kg (1.5 lbs.) with batteries
Size                                           225[L] x 103[W] x 59[D] mm (8.8[L] x 4.1[W] x 2.3[D] in.)
Safety:   This instrument is designed in strict compliance with safety standard IEC61010, overvoltage standard (CAT IV 600V) and pollution degree II.

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