Biddle 247000_series_UG 电路图.pdf

AVTM24-1J Rev A April 2006 Instruction Manual DLRO Digital Low Resistance Ohmmeters Catalog No. 247000 Series M Valley Forge Corporate Center 2621 Van Buren Avenue Norristown, PA 19403-2329 U.S.A. 610-676-8500 RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 DLRO Digital Low Resistance Ohmmeters Catalog No. 247000 Series RadioFans.CN 收音机爱 好者资料库 Copyright 2006 by Megger. All rights reserved. The information presented in this manual is believed to be adequate for the intended use of the product. If the product or its individual instruments are used for purposes other than those specified herein, confirmation of their validity and suitability must be obtained from Megger. Refer to the warranty information below. Specifications are subject to change without notice. WARRANTY Products supplied by Megger are warranted against defects in material and workmanship for a period of one year following shipment. Our liability is specifically limited to replacing or repairing, at our option, defective equipment. Equipment returned to the factory for repair must be shipped prepaid and insured. Contact your MEGGER representative for instructions and a return authorization (RA) number. Please indicate all pertinent information, including problem symptoms. Also specify the serial number and the catalog number of the unit. This warranty does not include batteries, lamps or other expendable items, where the original manufacturers warranty shall apply. We make no other warranty. The warranty is void in the event of abuse (failure to follow recommended operating procedures) or failure by the customer to perform specific maintenance as indicated in this manual. M Valley Forge Corporate Center 2621 Van Buren Ave Norristown, PA 19403-2329 610-676-8500 (Telephone) 610-676-8610 (Fax) AVTM24-1J Rev A April 2006 i Table of Contents 1.0 10 Ampere Systems .1 Section A INTRODUCTION.1 Section B SAFETY PRECAUTIONS.3 Section C RECEIVING INSTRUCTIONS.5 Section D SPECIFICATIONS.7 Section E CIRCUIT DESCRIPTION.15 Section F CONTROLS AND CONNECTIONS.19 Section G OPERATING PROCEDURE.23 Section H APPLICATIONS.27 Section I MAINTENANCE.31 Section J FIELD REPLACEABLE PARTS LIST.33 Section K WARRANTY the principal models are Catalog Numbers 247000, 247001, 247002. Part 2.0 describes the 100 Ampere systems including catalog numbers 247100, 247101 and 247120. The Catalog No. 247000 Digital Low Resistance Ohmmeter is a portable, rugged instrument that provides a direct-reading digital display of resistance in five ranges. It is powered by self-contained rechargeable batteries. A battery charger, operating from J1SV 50/60 Hz, is furnished in a separate package. The Catalog No. 247001 is similar to Catalog No. 247000 except that it has a built-in, line-operated charger. M AVTM24-1J REV A April 2006 2 The Catalog No. 247100 is a 100 Ampere Test System composed of a Catalog No. 247000 Measuring Module, and a Cat. No. 247120 100-amp power supply. The Catalog No. 24701 is also a 100 ampere test system. The ohmmeter has four terminals for a Kelvin connection to the sample under test, and it is recommended that Biddle test leads shown in Bulletin 24-1 be used with this instrument. Panel features include a two-position on-off switch that allows continuous or momentary operation, and on the rechargeable battery models a meter to indicate relative state of charge of the internal batteries. A prop is provided to keep the lid in a partly open position so that it can be used as a sunshade when reading the digital display in bright sunlight. The Catalog No. 247002 is similar to Catalog No. 247001 except that it has an extra 600 range. AVTM24-1J REV A April 2006 3 Section B SAFETY PRECAUTIONS SAFETY IS THE RESPONSIBILITY OF THE USER La seguridad es la responsabilidad del operador F WARNING Do NOT connect this instrument to energized circuits. The Digital Low Resistance Ohmmeters have been designed and constructed to meet the requirements of ANSI/ISDA S82.01-1994. There is no shock hazard from the instrument itself and it may be used freely in wet or outdoor environments. The line-operated battery charger and the A.C. supply, however, should be used and maintained by trained personnel who are familiar with the usual precautions for handling line-operated equipment. F DO NOT USE IN EXPLOSIVE ATMOSPHERE (This includes poorly ventilated battery rooms and enclosures.) M AVTM24-1J REV A April 2006 4 M AVTM24-1J REV A April 2006 5 Section C RECEIVING INSTRUCTIONS READ COMPLETELY BEFORE OPERATING Your Digital Low Resistance Ohmmeter has been thoroughly tested and inspected to rigid specifications before being shipped and is ready for use. Check the equipment received against the packing list. Notify Megger, Norristown, PA 19403 of any shortage of materials. The instrument should be examined for damage received in transit. If any damage is found, file a claim with the carrier at once and notify Megger or its nearest representative giving a detailed description of the damages observed. Charge batteries overnight before initial use of instrument. Refer to Section G for charging procedure. Check for correct operation of the instrument by connecting it to a resistor of known value. See Section G, Operating Procedure. M AVTM24-1J REV A April 2006 6 Catalog No. 247000 with Charger Catalog No. 247001 Catalog No. 247101with Charger Figure 2: Various DLRO Unit Combinations AVTM24-1J REV A April 2006 7 Section D SPECIFICATIONS Ranges, Resolution, Accuracy or 0.165 amps at 230 volts, 50/60 Hz. Fuse ratings: 115V-0.2A Slow Blow 230V-0.1A Slow Blow CONTINUOUS OPERATING TIME BETWEEN CHARGES CONTINUOUS OPERATING TIME WHILE ON CHARGE RANGE MEASURING CIRCUIT BATTERY DISPLAY BATTERY MEASURING CIRCUIT BATTERY DISPLAY BATTERY 6 mO 1 Hour 15 Hours 1 Hour No Limit 60 mO 10 Hours 15 Hours No Limit No Limit 600 mO 100 Hours 15 Hours No Limit No Limit 6 O 1000 Hours 15 Hours No Limit No Limit 60 O 1000 Hours 15 Hours No Limit No Limit Battery Life: Approximately 300 full charge- discharge cycles. Specifications AVTM24-1J REV A April 2006 11 Safety: Meets all applicable requirements of ANSI/ISA S82.01-1994. Highest voltage existing (except in charger primary and line supply primary) is 6 volts. Case: The measuring unit and charger have rugged molded case with handles and removable hinged lids. The measuring unit lid can be used as a sun shield. The charger case has similar construction with additional space for storing test leads. Test Lead Terminals: 5/16” diameter studs with wing nuts for spade or ring lugs. Dimensions and Weights: Cat. No. Weight Dimensions lbs kg inches cm 247000 11 5.01 8-7/8W x 8-1/8D x 8-1/8H 22.4 x 20.6 x 20.6(Instrument) 247000-47 - - 8-1/8W x 8-1/8D x 7-3/8H 22.4 x 20.6 x 18.8 (Charger) 247001 12.1 5.5 12W x 9 5/8D x 6 3/8H 30 x 24.5 x 16.2 247002 12.2 5.5 12W x 9 5/8D x 6 3/8H 30 x 24.5 x 16.2 M AVTM24-1J REV A April 2006 12 Catalog Numbers and Unit Combinations for 10-Ampere Systems CATALOG No. DESCRIPTION 247000 Instrument with Internal Rechargeable Batteries and separate 115V 50/60 Hz Charger Unit. Range: 0 to 60 Ohms in 5 ranges, 0 to 5.999 Milliohms lowest range (Note 1). 247000-3 Same as Cat. No. 247000 except with 100A adapter plug. 247000-47 Same as Cat. No. 247000 except with 230V-50/60 Hz charger. 247000-3-47 Same as Cat. No. 247000-47 except with 100A adapter plug. 247001 Same as Cat. No. 247000 except in single case. 247002 Same as Cat. No. 247001 except with an extra 600 range. Specifications AVTM24-1J REV A April 2006 13 Catalog Numbers and Unit Combinations for 10-Ampere Systems CATALOG No. DESCRIPTION 247100 See Part 2.0 247101 See Part 2.0 247120 See Part 2.0 NOTES: Note 1: Leads not included. (See Bulletin 24-1 for recommended test leads.) See Page 36 for information concerning 100-Ampere systems. M AVTM24-1J REV A April 2006 14 M AVTM24-1J REV A April 2006 15 Section E CIRCUIT DESCRIPTION Ra and RA set the test current to the values listed in Section 0, Specifications; there is a pair of these resistors for each range. On the 6 m 10A range, test current is also affected by the resistance of the test leads connected to the C1and C2 terminals. The instrument is designed to operate with current leads having a resistance of O.02 each. Using leads that have a resistance other than 0.02 will not affect the accuracy of the instrument, but will cause the test current to be different. A digital meter, powered by four size D nickel cadmium cells, displays the ratio: REF IN E E 6 EIN is the voltage across Rx where the potential leads are connected. (There are no length restrictions on the potential leads). EREF. scaled down by divider RD-RE, is set by the range network and represents the current in Rx. The calibration network on each range is set to produce, at the specified test current, nominally 60 mV at the EREF input. Consider a test specimen, Rx of 1.5 milliohms and a test current of 10 amperes. M AVTM24-1J REV A April 2006 16 The display would be: )m(500.1 V060.0 A100015.0 6= If the test current is reduced to 9 amperes: )m(500.1 V054.0 A90015.0 6= Thus the reading is independent of test current variations caused by changes in battery voltage, or by different test lead resistance. The digital meter has an “auto-zero circuit that normally holds any zero offset drift to one or two least counts, and a dual-slope integrating converter that is tuned to reject line frequency interference, either 50 Hz or 60 Hz. The battery charger supplied with models having internal rechargeable batteries is a constant-current type specifically intended for use with nickel-cadmium batteries. There are two charging circuits: one that supplies 0.4A to charge the display battery, and another with two branches that supplies 0.7A to each of the two measuring circuit batteries. These current values are the battery manufacturers recommended “ten-hour rates” and represent a safe charging level that will not damage the Circuit Descriptions AVTM24-1J REV A April 2006 17 batteries, even if they are allowed to remain on charge indefinitely. Charging currents are set at the factory and need readjustment only when batteries are replaced. Zener diodes protect the instrument from damage caused by switching transients that may occur when measuring the resistance of inductive samples, and by 60 Hz pickup that may occur when measuring large equipment in high voltage switchyards. M AVTM24-1J REV A April 2006 18 M AVTM24-1J REV A April 2006 19 Section F CONTROLS AND CONNECTIONS Fig. 3 shows a front panel view of Catalog No. 247000 with functional parts and operating controls labeled. S4, M1 Battery test meter M1 shows the relative state of charge of the internal rechargeable batteries. With S4 in the “Display” position Ml is connected to the battery that powers the digital meter. With S4 in the “measure position, M1 is connected to the measuring circuit battery. This test is valid only when the instrument is operating and connected to a test specimen or with the C1and C2 leads shorted. When the pointer indicates in the red zone the batteries should be recharged. S3 - The ON/OFF switch has two “ON” positions: a “lock” position for continuous operation, and a “momentary” spring-held position that helps conserve battery power when taking a series of readings on the high-current ranges. S1 - The range switch selects one of five resistance ranges. Panel markings are fullscale values; nominal test currents are shown in parentheses. M2 A 3 digit red LED display shows the resistance of the specimen under test. It is direct reading with decimal points selected by a deck on the range switch. M AVTM24-1J REV A April 2006 20 C1, P1, P2, C2 Four terminals with wingnuts are provided for making a Kelvin connection to the specimen under test. Test current is available at the C1 and C2 terminals, and the actual resistance is measured between the points where leads connected to the P1 and P2 terminals are placed. S2 The “forward-reverse” switch interchanges the P1 and P2 connections internally. In the “reverse” position, the digital meter sees a voltage of opposite polarity. The purpose is to enable an operator to average the forward and reverse readings if a zero offset error is suspected. J2 The optional external power connector must have its jumper plug (chained to the instrument) in place while the instrument is in normal use. When charging the internal batteries, remove the jumper plug and connect the charger to J2. Controls disregard this when calculating the average. ? Sunshade To aid in reading the digital display in bright sunlight, use the prop on the lid to hold it tilted partially open as a sunshade. 1. Using Duplex Clamp leads on a circuit breaker or transformer. 2. Using Duplex Hand Spikes on a motor commutator. Operating Procedure AVTM24-1J REV A April 2006 25 3. Using Kelvin Clip leads. Figure 4: Typical Connections to a Test Sample. 4. Charging Batteries To charge the batteries, remove the jumper plug from J2 and connect the output lead of the battery charger to J2. A pilot light on the charger will indicate when it is connected to an energized ac power line. Charging time for fully discharged batteries is 14 hours or overnight. The instrument may be used continuously (except on the 10A range, where battery life limitations apply) while its batteries are charging. M AVTM24-1J REV A April 2006 26 M AVTM24-1J REV A April 2006 27 Section H APPLICATIONS MEASURING CONTACT RESISTANCE OF CIRCUIT BREAKERS Biddle Cat. No. 241004-18 Duplex clamp leads are recommended for this application. Connect the leads as shown in Fig, 3. For safety, one terminal of the sample must be grounded. MEASURING WINDING RESISTANCE OF MOTORS and OTHER APPLICATIONS F WARNING When the test current through a transformer winding is switched off, the energy stored in the magnetic field must be dissipated. The DLRO instrument provides a path to harmlessly dissipate this energy when the current is interrupted by the On/ Off switch. It is not recommended to use a DLRO for measuring transformers and other large inductive devices. The transformer ohmmeter is specifically designed for inductive devices. M AVTM24-1J REV A April 2006