Instruction manual Compact Insulation resistance tester with 2-range KEW MEG series MODEL3144A, 3145A, 3146A, 3147A, 3148A KYORITSU ELECTRICAL INSTRUMENTS WORKS,LTD.
Contents 1．Safety warnings ……………………………………………………１ 2．Features ……………………………………………………………３ 3．Specification ………………………………………………………４ 4．Instrument layout …………………………………………………７ 5．Preparation for measurement ……………………………………８ 5−1 Mechanical zero adjustment ………………………………８ 5−2 Test lead connection ………………………………………８ 5−3 Battery voltage check ………………………………………９ 5−4 Power-on-indication LED …………………………………９ 6．Measurement ………………………………………………………10 6−1 AC voltage measurement …………………………………10 (Mains disconnection check) 6−2 Insulation resi
１．Safety warnings ○ This instrument has been designed, manufactured and tested according to IEC 61010-1: Safety requirements for Electronic Measuring apparatus, and delivered in the best condition after passed the inspection. This instruction manual contains warnings and safety rules which must be observed by the user to ensure safe operation of the instrument and retain it in safe condition. Therefore, read through these operating instructions before using the instrument.
DANGER ¡Never make measurement on a circuit in which the electrical potential exceeds following values. MODEL3144A/ 3147A : AC/DC600V MODEL3145A/ 3146A/ 3148A: AC/DC300V ¡Do not attempt to make measurement in the presence of flammable gasses. Otherwise, the use of the instrument may cause sparking, which can lead to an explosion. ¡Never attempt to use the instrument if it's surface or your hand are wet.
２．Features MODEL3144A, 3145A, 3146A, 3147A, 3148A are two-range insulation resistance testers for testing low-voltage installation. ¡Designed to following safety standards: IEC 61010-1, IEC 61010-031, IEC 61557 ¡Small and light weight. ¡Auto-discharge function When insulation resistance like a capacitive load is measured, electric charges stored in capacitive circuits are automatically discharged after measuring. Discharge can be checked with the meter.
３．Specification ¡Applicable standards IEC 61557 IEC 61010-1 Measurement CAT.III 300V/ CAT.II 600V Protection class II Location for use: altitude 2000m or less IEC 61010-031 IEC 60529 IP40 ¡Measuring range and accuracy 3147A 3145A 3148A 3146A 50V 125V 250V 3144A MODEL Nominal voltage Max.
Operating error (B) is an error obtained under the nominal operating conditions, and calculated with the intrinsic error (A), which is an error of the instrument used, and the error (En) due to variations. According to IEC61557, the maximum operating error should be within +/-30%. Ｂ ＝︱Ａ︱＋ 1.
Temperature & humidity range Storage temperature & humidity range Insulation resistance Withstand voltage : 0℃∼40℃ (RH: 85% or less) (no condensation) : -20℃∼＋60℃ (RH: 75% or less) (no condensation) : at least 50MΩ/ DC500V between the electrical circuit and the enclosure : AC3700V(50/60Hz) for 1 min. between the electrical circuit and the enclosure Overload protection Insulation resistance range: 50V/ 100V/ 125V/ 250V 300V (50/60Hz) for 10 sec. 500V 600V (50/60Hz) for 10 sec. AC voltage range: Max.
４．Instrument layout Fig.
５．Preparation for measurement 5−1 Mechanical zero adjustment With the Range switch set to the OFF position and without pressing the Test button, turn the Zero adjuster with a screwdriver so that the pointer lines up with the "∞" mark on an insulation resistance scale. In case the instrument is used at the sloping place, ensure that the pointer lines up with the "∞" mark tilting the instrument to the necessary angle.
CAUTION Instrument doesn't operate without connecting the test lead even if the Test button is pressed down. Battery check and operation check are not available without connecting the test lead. The Backlight function is available at any time. 5−3 Battery voltage check (1) Connect the test lead to the instrument, and set the Range switch to the BATT. CHECK position. (2) Press the Test button or Remote control switch.
６．Measurement 6−1 AC voltage measurement (Mains disconnection check) The AC voltage measurement function is available on any ranges. (1) Connect the Earth probe to the earth of the circuit under test and Line probe to the other side. If the circuit is not earthed, connect Earth probe to any appropriate conductor. (2) Without pressing the Test button or Remote control switch, take the reading on the AC voltage scale.
This instrument also provides simplified measurement of DC voltage. Multiplying 0.9 by the indicated value at AC voltage scale provides the DC voltage value. However, the polarity isn't indicated. DC voltage (V) = Indicated value at AC voltage scale x 0.9 (V) 6−2 Insulation resistance measurement Before performing any insulation test, check the maximum voltage that may be applied to the circuit under test.
(1) Check the maximum voltage that may be applied to the circuit under test. Set the Range switch to a desired insulation resistance range. (2) Connect Earth probe to the earth terminal of the circuit under test. If the circuit is not earthed, connect Earth probe to any appropriate conductor. (3) Connect Line probe to the circuit under test and press the Test button or Remote control switch. (4) Take the reading on the scale for the selected insulation resistance range.
This function allows electric charges stored in the capacitance of the circuit under test to be automatically discharged after testing.Discharge can be monitored by the AC voltage reading. (6) Set the Range switch to the OFF position, and disconnect the probes from the instrument. 6−3 Continuous measurement For continuous measurement, a lock-down feature is incorporated on the Test button.
Output voltage(V) M-3144A Output characterisstics Note) For the output characteristics of M3147A,see the left graph for.M3144A(at 500V)and 3145A(at 125V). Output voltage(V) Insulation resistance M-3145A Output characterisstics Note) For the output characteristics of M3148A,see the left graph for.M3145A.
6−5 Backlight function To facilitate working in dimly lit situations, a backlight function is provided which illuminates the scale plate. Press the backlight switch to operate this function. The backlight will light up for about 60 sec., and then turned off automatically.
7．Battery replacement DANGER Never open the Battery cover during a measurement. WARNING To avoid possible electric shock, remove test leads before opening the Battery cover. After replacing batteries, be sure to tighten up the screws for Battery cover. CAUTION Do not mix new and old batteries. Install batteries in correct polarity as marked inside the Battery compartment. (1) Set the Range switch to "OFF" position, and remove the test leads from the instrument.
8．Notes on Housing case and accessories 8−1 Case lid Case lid can be fit under the Housing case while making measurement. (1) Unhook and open the Case lid. (2) Turn it 180 degrees. (3) Put the Case lid under the Housing case. (4) Hook it on to the Housing case.
8−2 Neck strap and Cord case This instrument is equipped with a strap to suspend from the neck to allow both hands to be used freely for easy and safe operation. (1) How to fix the belt Neck strap Pull up the belt.
8−3 Test prods and replacement 1. Types of Test prods MODEL8072:Standard Test prod Used for ordinary measurement. (Attached to the Line probe at the time of purchase.) MODEL8017:Extension probe Used in difficult-to-reach situations. MODEL8016:Pickle prod (Optional) Used to hook the probe on a conductor. 2. How to replace Test prod To remove the Test prod, turn the cap of LINE probe counterclockwise. Insert the threaded end of another prod into the hexagonal hole on the probe cap as shown.
8−4 Adaptors for the Earth cord and replacement 1. Adaptors MODEL7131:Safety alligator clip Connected to the Earth terminal of the Earth terminal board. MODEL7101:Flat test bar Connected to the earth side of the outlet. 2. How to replace Adaptors To remove the adaptors, pull them out. Then firmly attach the adaptor as desired to the tip of the Earth cord.
8−5 Cleaning Meter cover This instrument is managed by our company's quality standard and is delivered in the best condition after passed the inspection. But in the dry time of winter static electricity sometimes builds up on the meter cover due to the characteristic of plastic. When static builds up on the meter cover and affects the meter reading, use a cloth damped with off-the-shelf anti-static agent or detergent to wipe the meter cover surface.
DISTRIBUTOR KYORITSU ELECTRICAL INSTRUMENTS WORKS, LTD. No.5-20, Nakane 2−chome,Meguro-ku, Tokyo, 152-0031 Japan Phone:81−3−3723−0130 Fax:81−3−3723−0152 URL:http://www.kew-ltd.co.jp E-mail:info@kew-ltd.co.
