INSTRUCTION MANUAL MODEL 157 AC/DC LEAKAGE CURRENT TESTER a world leader in test & measurement FINE INSTRUMENTS CORPORATION Room # 601, DAEWOO TECHNOPIA, 768-1, WONSI-DONG, DANWON-GU, ANSAN-SI, GYEONGGI-DO, SOUTH KOREA - TEL: (82-31) 470-8888 - FAX: (82-31) 470-8887 - E-mail: fine@finest.co.kr - Internet: www.finest. co.kr Copyright 2000 Fine Instruments Corp. All right reserved. Specifications subject to change without notice. Litho in Korea. FINE INSTRUMENTS CORPORATION
Table of Contents 1. Introduction 2. Safety 3. Technical Specifications 4. Operating Instructions 5. How to Measure 6. Maintenance and Calibration 1 2 4 7 9 16 SOURCES LIKE SMALL HAND-HELD RADIO TRANSCEIVERS, FIXED STATION RADIO AND TELEVISION TRANSMITTERS, VEHICLE RADIO TRANSMITTERS AND CELLULAR PHONES GENERATE ELECTROMAGNETIC RADIATION THAT MAY INDUCE VOLTAGES IN THE TEST LEADS OF THE MULTIMETER. IN SUCH CASES THE ACCURACY OF THE MULTIMETER CANNOT BE GUARANTEED DUE TO PHYSICAL REASONS. 1. Introduction This Meter is a handheld battery operated AC/DC Leakage Current Tester that is designed to measure the AC/DC leakage current and high current up to 40A. This Meter is designed and tested according to IEC Publication 1010-2-032 (1994-12)(Overvoltage Category lll) and the EMC Directive (EN 50081-1 and EN 50082-1) and other safety standards (see Technical Specifications ). This Meter has a frequency filtering function for measuring currents of fundamental frequency. This filter function can be used when we check whether the leakage breaker was tripped by leakage currents or by effects of harmonics. This Meter provides : Shielded transformer jaws to minimize the effect of external stray magnetic field 2A AC range with the 1mA best resolution Can measure from 1 ma to 40A AC Auto Ranging for Volts and Ohms Manual Ranging for AC/DC Amperes Can accurately measure leakage current from high frequency electric appliances such as inverters 1
DC Amps Zero Adjustment function Data hold function Law battery indicator Automatic Power off after 10 minutes inactivity in any measurement function Frequency Response Range : 50Hz to 400Hz 2. Safety Read the following safety information carefully before attempting to operate or service the Meter. Although the Meter is designed to be as safe as possible, safety in use is the responsibility of the operator who must be suitably qualified and/or authorized. Maximum voltage between current carrying conductors, which are uninsulated, and ground must not exceed 600V RMS. Always choose an insulated conductor if available. Do not attempt to measure any current or voltage higher than the maximum limits of the input values shown in the electrical specifications. Never measure any current while the test leads are inserted into the input jacks. Never use the Meter or test leads whose insulating protection has been impaired. Be extremely cautious when clamping around uninsulated conductors or bus bars. Never leave the Meter to contact with any surface water. Ingress of water could damage the electronics as well as cause a potential shock hazard. Accidental contact with the conductor could result in electric shock. Frequently inspect the Meter and the test leads for damage. If the Meter is physically damaged or does not function correctly, don t use it. Avoid working alone with high voltage circuits. Use the meter only as specified in this manual. Otherwise, the protections provided by this Meter may be impaired. When taking measurements in high voltage circuits, connections should be made to the circuits while the power is off. Safety Symbols Warning There is a risk of electrical shock. Caution Refer to this manual before using this meter. Double Insulation The meter is protected throughout by double insulation or reinforced insulation. When servicing, use only specified replacement parts. CAT III - Installation category (overvoltage category) lll according to EN 61010-1 and EN 61010-2-032 Alternating Current (AC) Only use the FTL-500V1 test lead supplied by Fine Instruments Corporation. Disconnect the live test lead before disconnecting the common test lead. 2 Direct Current (DC) Both DC and AC Earth Ground 3
4 3. Technical Specifications 3.1 General Specifications Digital Display (LCD) : Counts 4000 Updates 3 times/sec. Maximum Volts to Ground : 600V RMS Overflow Indication : LCD will show an OFL Low Battery Indication : The is displayed when the battery voltage drops below the operating voltage. Battery Life : 60 hours typical (alkaline) Battery Type : NEDA 1604A 9V or 6LF 2 9V Maximum Jaw Opening : 36mm Maximum Conductor Size : ø 33mm Maximum Conductor Voltage: 600V RMS Indoor use Storage Temperature : -10 C to 50 C Operating Temperature : 0 C to 45 C at and Humidity R.H < 80% non-condensing Aititude : 2,000m Relative Humidity : 0% to 80% at 32 F to 95 F (0 C to 35 C ) 0% to 70% at 95 F to 115 F (35 C to 45 C ) Pollution Degree : 2 Safety Conformance : Conforms to the requirements of UL 3111-1, CSA C22.2 No.1010.1-92 and ANSI/ISA-S82.01-94 Weight : Approx. 320g Size : 190 (L) x 76.8 (W) x 42.5 (D)mm Standard Accessories : Battery (9V), Instruction manual, test leads and soft carry case 3.2 Electrical Specifications Accuracy is given as ±([% of reading] + [number of least significant digits]) at 18 C to 28 C with a relative humidity of up to 80%, for a period of one year after calibration. AC/DC Current FUNCTION RANGE RESOLUTION ACCURACY DC A AC A (50Hz to 400Hz) 2 A * 40 A 2 A * 40 A 1 ma 10 ma 1 ma 10 ma 2.0% + 20 1.5% + 10 2.0% + 30 2.0% + 5 OVERLOAD PROTECTION 600V RMS Filtering Function for Measuring Currents of Fundamental Frequency The Filtering function can make the Meter measure currents of fundamental frequency range when the Filter switch is at the ON position. The fundamental frequency range (Filter ON position) has the frequency characteristics for the limited frequency range of 50Hz to 100Hz and the wide frequency range (Filter OFF position) has the frequency characteristics for the frequency range of 50Hz to 400Hz. This Filtering function is very useful for checking whether the currents contain harmonics or not. Recently there has been increased usage of power through inverters, switching regulators, etc. When the high frequency noise from such appliances leaks or flows into the ground through capacitors not filtering completely, the earth leakage breaker may not trip. In such a case the Meter may not give correct current readings with the Filter switch at the ON position. Therefore, it is necessary to make current measurements with the Filter switch at the OFF position. 5
When in doubt as to the presence of high frequencies and harmonics that affect AC current measurements, take current readings with the switch at the ON and OFF positions respectively and then compare the results obtained. Effect of External Stray Magnetic Field 50mA AC max. in proximity to 100A AC carrying, ø10mm conductor 4. Operating Instructions 4.1 Controls and Indicators (1) CLAMP. Opens 36mm to enclose conductors. (2) LEVER. Open the close clamp jaws. AC/DC Volts FUNCTION RANGE RESOLUTION ACCURACY INPUT IMPEDANCE 4V 1mV DC V 40V 10mV 400V 100mV 0.9% + 2 600V 1V 10MΩ 4V 1mV AC V 40V 10mV (50Hz to 1.5% + 3 400V 100mV 400Hz) 600V 1V Ohms FUNCTION RANGE RESOLUTION ACCURACY OVERLOAD PROTECTION 400Ω 0.1Ω 4kΩ 1Ω 0.9% + 3 40kΩ 10Ω Ohms 600V RMS 400kΩ 100Ω 4MΩ 1kΩ 40MΩ 10kΩ 1.2% + 5 (1) (2) (4) (5) (6) (3) (9) (10) Continuity Beeps less than approximate 50Ω (7) (8) 6 7
(3) POWER ON / FUNCTION SELECTION SWITCH. Turns power on and selects functions. Always set the switch to the OFF position after use. (4) MODE. Toggles between AC mode and DC mode in the either Amperes or Volts measurement range. Toggles between mode and Ω mode in the / Ω range. (5) DATA HOLD (DC A ZERO). Freezes reading in digital display. Press this button for 2 seconds in the DC amperes measurement mode to initiate the Zero Adjustment procedure. (6) LCD. 3 3/4 digit, liquid crystal display with maximum indication of 3999. Function symbols, decimal points, (negative) indicator or low battery indicator appears automatically. OFL is displayed for overrange indication. (7) COM. Common Terminal. (8) VΩ. Volts or Ohms Input Terminal. (9) CURRENT RANGE SWITCH. Selects between 4A and 40A range in the AC/DC amperes measurement mode. (10) FILTER ON/OFF SWITCH. Selects between FILTER ON and FILTER OFF in the AC amperes measurement mode. 5. How to Measure 5.1 Before using the Meter, familiarize yourself with the instrument and this manual. READ AND REVIEW THIS MANUAL FREQUENTLY. 5.2 Visual Inspection of the Meter Before use, inspect the Meter for any conditions which would make it unsafe. Check for missing or loose parts. Check also for damage. Make certain that the Meter is free from oils, grease, dirt and excessive moisture. IF ANY OF THESE CONDITIONS ARE FOUND, DO NOT USE THE METER. 5.3 Visual Inspection of the Test Leads Before use, check the test leads for deterioration of the insulation. IF THE TEST LEADS ARE IN ANY WAY DAMAGED OR DEGRADED, DO NOT USE THEM. THEY MUST BE REPLACED. Replace the battery before using the Meter when the low battery indicator is displayed on the LCD. If the Meter does not turn ON, the battery is missing or worn out. To replace the battery, see Battery Replacement of section 6. The Meter shuts OFF after 10 minutes if no pushbutton is pressed, even though it is making a measurement in any measurement function. 8 9
5.4 Measuring AC Current THE METER IS NOT DESIGNED TO MAKE CURRENT MEASUREMENTS ON CIRCUITS WITH VOLTAGE ABOVE 600V AC. MEASUREMENTS ON CIRCUITS ABOVE THIS VOLTAGE MAY CAUSE SHOCK HAZARD AND DAMAGE TO THE METER OR EQUIPMENT UNDER TEST. For measurements of earth leakage current and small current that flow through a grounded wire, refer to Fig.2. It is recommended that 4A range is used for these measurements. 1. Put the Meter in the desired AC amperes range. 2. For normal measurements, refer to the Fig.1. or (CORRECT METHOD) Fig.2 Leakage Current Measurements on the Single Phase Systems For measurements of unbalanced leakage current, clamp the jaws around all the current carrying conductors except a grounded wire. Refer to the Fig. 3. (WRONG METHOD) Fig.1 Normal AC Current Measurements 10 11
THE TRANSFORMER JAWS ARE MADE OF METAL AND THEIR TIPS ARE NOT INSULATED. THEREFORE, IT IS VERY DANGEROUS TO TOUCH THE METAL SECTION OF EQUIPMENT UNDER TEST WITH THE JAW TIPS. BE EXTREMELY CAREFUL WHEN CLAMPING AROUND A BARE CONDUCTOR. (3 Wires System without Neutral) 5.5 Measuring DC Current For normal measurements, 1. Put the Meter in the desired DC amperes range. 2. Set the Meter display zero value by pressing the Data Hold button for 2 seconds. 3. Press the lever to open the clamp jaws and clamp around a conductor. (If necessary, use the arrow direction mark to identify the direction of DC current flow.) 4. The measured current will appear on the display of the meter. (4 Wires System With Neutral) For measurements of DC leakage current, repeat the above 1 to 3 referring to the Fig.2 and Fig.3 of 5.4 above. Fig.3 Leakage current Measurements on the Three Phase Systems It is recommended that the conductors are placed at the center of the closed jaws as much as possible. 3. If you want to measure currents in the fundamental frequency range only, set the Filter switch to the ON position 4. Set the Power/Function switch to the OFF position after using the Meter. 12 13
5.6 Measuring AC (or DC) Volts TO AVOID THE RISK OF ELECTRICAL SHOCK, INSTRUMENT DAMAGE AND/OR EQUIPMENT DAMAGE, INPUT VOLTAGES MUST NOT EXCEED 600 VOLTS AC (or DC). DO NOT ATTEMPT TO TAKE ANY UNKNOWN VOLTAGE MEASUREMENTS THAT MAY BE IN EXCESS OF 600 VOLTS AC (or DC). 1. Put the Meter in the Volts AC (or DC) range. 2. Plug the red test lead into the VΩ input terminal and the black test lead into the COM input terminal of the Meter. 3. Disconnect the power from the circuit to be tested. 4. Connect the test leads to the circuit to be tested. 5. Reapply power to the circuit. The measured voltage will appear on the display of the Meter. 6. When measuring DC volts only, if the red test lead is connected to the negative (or lower voltage) side of the circuit, a minus indicator will appear on the left hand side of the LCD. 5.7 Measuring Resistance (Ohms, Continuity) 1. Set the Function switch to the /Ω position. 2. Insert the black test lead into the COM input terminal and the red test lead into the VΩ input terminal. 3. Connect the test leads to the circuit to be measured. 4. The measured resistance will be displayed. Audible Continuity Buzzer 1. Set the Function switch to the /Ω position and select the continuity test mode by pressing the MODE button. 2. Insert the black test lead into the COM input terminal and the red test lead into the VΩ input terminal. 3. Connect the test leads to the circuit to be tested. 4. The Meter will emit a continuous tone for resistances of less than 50 ohms. Data Hold 1. Obtain a stable reading on any function or range of the Meter. 2. Press the Data Hold button. (HOLD will be displayed.) 3. The reading will be frozen on the display until the Data Hold button is pressed again. Auto-Power-Off The Meter automatically shuts off after 10 minutes of inactivity. CAUTION TURN OFF POWER AND DISCHARGE ALL CAPACITORS ON CIRCUIT TO BE TESTED BEFORE ATTEMPTING IN-CIRCUIT RESISTANCE MEASUREMENTS. FAILURE TO DO SO MAY END UP IN EQUIPMENT AND/OR INSTRUMENT DAMAGE. 14 15
6. Maintenance and Calibration Battery Replacement IF THIS METER IS USED IN A MANNER NOT SPECIFIED BY THIS MANUAL, THE PROTECTION PROVIDED BY THE EQUIPMENT MAY BE IMPAIRED. REPAIRS OR SERVICING NOT COVERED IN THIS MANUAL SHOULD ONLY BE PERFORMED BY QUALIFIED PERSONNEL. TO AVOID ELECTRICAL SHOCK, DO NOT SERVICE UNLESS YOU ARE QUALIFIED TO DO SO. Cleaning and Decontamination Periodically clean your meter s case using clamp cloth. Do not use abrasives, cleaning solvents or strong detergents, as they may damage the finish or affect the reliability of the structural components. TO PREVENT ELECTRICAL SHOCK HAZARD, TURN OFF THE METER. DISCONNECT ALL TEST LEADS AND UNCLAMP THE METER FROM ANY CONDUCTOR BEFORE REMOVING THE BATTERY COVER. 1. Unplug the test leads from the instrument. 2. Remove the screw from the battery compartment cover and lift the cover. 3. Replace the battery with the same type and size as the one removed. 4. After a battery change, this battery cover must be reinstalled and that it must not be discarded. 5. Reattach the battery compartment cover to the meter and reinstall the screw. Calibration Calibrate this Meter once a year to maintain its performance specifications. 16 17