PAT-Cal 2 TECHNICAL MANUAL

Transcription

1 Portable Appliance Tester Calibrator PAT-Cal 2 TECHNICAL MANUAL 1 Time Electronics Limited Botany Industrial Estate, Tonbridge, Kent, TN9 1RH. Tel: +44(0) Fax: +44(0) info@timeelectronics.co.uk Web Site: V1.6 02/10/01

2 2 CONTENTS page 1 INTRODUCTION Unpacking Front panel controls 4 2 SAFETY & GENERAL INFORMATION Safety Precautions PAT-Cal 2 Limitations General Information Battery Meter 7 3 OPERATION Calibrating PAT s EasyCal calibration software 9 4 CALIBRATION PROCEDURES Earth Bond Insulation Leakage Substitute leakage Touch Leakage Load Test Calibrating Insulation/Continuity Testers 16 5 SPECIFICATIONS Declaration of Conformance 19 6 FAULT DIAGNOSIS 20 7 GUARANTEE AND SERVICING 21

3 3 1 INTRODUCTION PAT-CAL 2 is an all in one calibration unit for Earth Bond, Insulation, Leakage, Touch Leakage and Load Test functions, providing rapid high accuracy calibration of PAT s (Portable Appliance Testers). PAT-Cal 2 is constructed in a high strength plastic case and is powered by a rechargeable battery. This ensures full isolation from the mains and prevents stray leakage, which can cause inaccuracies. The voltage and current are displayed on an LCD digital meter mounted on the front panel. 1.1 Unpacking Contents list The PAT-Cal 2 Calibrator comprises various components, which are delivered to the customer as a complete package. Unpack all items and check off against contents list below. Please report any shortages immediately. 1. PAT-Cal 2 including Earth Bond Stud cover 2. 4mm terminal box adapter 3. Technical Manual V Adapter 5. 16Amp IEC Connector (for external load) 6. Battery charger 7. Calibration Certificate (if specified on order) 4mm Terminal Box Adapter 110V Adapter

4 1.1 Front Panel Controls 4 External Meter Sockets ON/OFF Switch AC/DC Switch 1/10 Range Switch Battery Charging Connector Function Switch 4mm Touch Leakage Socket 16A IEC External Load socket

5 5 2 SAFETY & GENERAL INFORMATION 2.1 Safety Precautions Prior to using the PAT-Cal 2, the following precautions and recommendations should be noted. High Voltage: When PAT s or Insulation Testers are being calibrated, voltages up to 1000V may be present and users should be aware of the dangers involving serious electrical shock. High Current: During the Earth Bond calibration of a PAT, currents in excess of 30Amps may be present and users should be aware of the power levels involved. Warning: THE 13A PLUG ON THE PAT-Cal 2 IS FOR CONNECTION TO THE PAT ONLY AND MUST NOT BE CONNECTED DIRECTLY TO THE MAINS SUPPLY. The mains supply used for PAT calibration must be a permanent properly earthed supply. The presence of a good earth must be certified by a loop test at regular intervals. Temporary supplies or extension leads must not be used. The PAT to be calibrated must be tested as an appliance by another calibrated PAT and fully pass all appropriate tests before connection to PAT-Cal 2. The calibration procedure must be carried out in the correct order. When conducting Insulation or Leakage tests the Earth Bond Stud cover must be in place over all 10 studs. Only in this position will the interlock allow the test load to be applied. Also note that any exposed conductors (studs, earth clips etc.) on the PAT must not be touched. When conducting full voltage Earth Leakage calibration, if the open circuit voltage (OCV) reading is not within 10% of the nominal mains voltage, the calibration must be stopped. (This is an indication of a faulty earth)

6 6 2.2 PAT-Cal 2 Limitations Notes: High voltage limitation Some PAT s incorporate functions which cannot be tested using the PAT-Cal 2, e.g. Flash Tests. Due to the high voltage levels involved, the PAT- Cal 2 is not designed for checking this function and an alternative method should be used. Also, please note that PAT-Cal 2 is not constructed to withstand voltages in excess of 1000V AC or DC. Please refer to specifications. Load testing - minimum value Some PATs require there to be a minimum load connected before a test can be performed. If this is the case, a load of around 100W should be plugged into the EXTERNAL LOAD socket and the ROCKER SWITCH placed in the ON position. Circuit resistance tests PAT-Cal2 does not provide for this function. Where required it is recommended that a separate resistance box is used to simulate the required values. Time Electronics type 1051 or 1061 are suitable. In general the range from 1R to 10kR is required with an accuracy of 1% or better. Flash test function calibration As mentioned above, PAT-Cal2 does not provide this feature. To undertake this the user will require a high voltage ac meter (min 5kV) and various high voltage resistors (min 5kV rated). 2.3 General Information The PAT-Cal 2 simulates the loads which PAT s and INSULATION TESTERS encounter during testing of equipment. The following functions are selected by the large rotary Function switch in the centre of the PAT-Cal 2 panel: 1. Earth Bond 2. Insulation 3. Appliance Leakage 4. Touch Leakage 5. Load Test (metering only) It is recommended that the function switch is placed in the OFF position (located within the Load Test section) at the end of a calibration. To cater for different styles of connector, the following adapters are supplied with the PAT-Cal 2: a) For calibrating Insulation Testers an adapter is provided to allow 4mm test leads to be used. b) 110V Adapter is provided for connection to PAT s with 110V socket. PAT s from different manufacturers vary in their specifications and recommended test methods. It is suggested that the manufacturers specification is checked prior to calibration. The operation of the PAT under manual control must be fully understood before starting calibration

7 7 2.4 Battery The PAT-Cal 2 is powered by a rechargeable 6V NiCad battery pack which will give greater than 200hrs use. The PAT-Cal 2 is supplied with a 13A plug top charger, the battery should be recharged for 6 hours when the Low Batt symbol appears on the meter display. Note: The unit should not be used for calibration at the same time as the battery is being charged. Note: The PAT-Cal 2 has a power saving function which effectively shuts the unit down after approximately 15 minutes of inactivity. To restart, switch off and then on again 2.5 Meter The PAT-Cal 2 is fitted with an internal digital meter and 4mm shrouded sockets to which an external meter can be connected. The output across these sockets is always 200mV full scale and is AC or DC depending on the measurement selected by the main function switch. The BLACK socket may be connected to mains earth or mains neutral. This connection should be considered as potentially hazardous and this should be born in mind when connecting an external measuring device. When measuring AC the meter uses a true RMS device which may give a reading of between 0 and 10 on the meter when the input is zero. This is the normal operation of the RMS converter and is not an error condition. There are three buttons below the meter. ON/OFF Switches the meter on or off. If the function switch remains in the same position for more than 15 mins the meter will go into power save mode. Press the ON/OFF button twice or move the function switch to return to normal on mode. Note: Ensure the meter is switched off after use. Note: The Touch Leakage current generator is switched on and off independently by the main Function Switch. AC/DC If the PAT being calibrated uses DC instead of AC for a test, pressing this button will toggle the meter between AC and DC measurements. 1/10 SCALE If the meter reading is below 199, pressing 1/10 SCALE will increase the meter sensitivity. The decimal point will be moved to indicate the new scale. Both AC/DC and 1/10 SCALE selections are reset to the default when the main function switch is moved.

8 3 OPERATION Calibrating PAT s Test the PAT to be calibrated as an appliance. Ascertain which calibrations are required and select the manual or calibration mode for the PAT. Plug the PAT-Cal 2 s 13A plug into the appropriate connector on the PAT being calibrated. Use the adapter if the 110V connector is required. Connect the PAT to the mains supply and switch on. Switch on the PAT-Cal 2 meter. The pushbutton switch is located below the meter display. Carry out the calibration procedures as described in the next section. Note: Ensure that the PAT does not attempt a Flash Test at any time.

9 9 3.2 EasyCal Users with Time Electronics' EasyCal calibration systems should contact Time Electronics for example procedures for some of the most common PAT s. For site work EasyCal can be loaded onto a lap-top PC and the results data entered manually. If a small ink-jet printer is available, the calibration certificates can be printed out on-site. EasyCal 5 - CALIBRATION SOFTWARE Extended range of instruments and equipment that EasyCal can calibrate. Fully automatic closed loop calibration. The Universal Read-Back function allows you to automate calibration by letting EasyCal control a wide range of programmable and data read-back instruments and test equipment. You can connect existing calibration equipment (GPIB or RS232 interface) to an EasyCal system and will be up and running in no time using the straightforward, user friendly, procedures. The standard Time Electronics CalRun is used for the actual calibration and the results data is stored on the PCs hard drive. Certificates printed immediately in standard format or re-designed to your requirements. Uncertainty calculator - to the new ISO standard Electronic signatures for full traceability of stored results Conditional tests for closed loop calibration Repeat cal points with max, min, rms or std dev, results Calibration Manager - reminder letters, pre-cal sheets User definable conversion tables standard procedures SiteCal - full documenting for away from lab calibration

10 10 4 CALIBRATION PROCEDURES 4.1 Earth Bond High Current AC Earth Bond for test currents of 2 50A Within the Earth Bond HIGH CURRENT section of PAT-Cal 2. Select O/C V on main function switch - Connect PAT Earth Bond Clip to O/C V stud, operate PAT control and note PAT-Cal 2 meter reading. The open circuit voltage is measured, Range 0 to 20V AC. Select CAL on main function switch. Connect the Earth Bond Clip to the S/C I stud, operate PAT control. The short circuit current is measured, Range 0 to 50 Amps AC. Connect Earth Bond Clip to Earth Bond studs in turn (20, 50, 100, 200, 500, milliohms 1, 2, 4, 9, Ohms), operate PAT control and note PAT meter readings. Note: Due to the drive voltage limitations and internal resistance of many PAT s (see PAT manufacturers handbook), it may not be necessary to calibrate earth bond at the higher resistance values. Note: Due to internal heating effects in the PAT-Cal 2, it is recommended that the high current earth bond tests be completed as quickly as possible. A maximum of 10 seconds applied to each stud is recommended.

11 11 Low Current AC Earth Bond for test currents of less than 2A Within the Earth Bond LOW CURRENT section of the PAT-Cal 2 Select O/C V on main function switch. Connect PAT Earth Bond Clip to O/C V stud, operate PAT control and note PAT-Cal 2 meter reading. The open circuit voltage is measured, Range 0 to 2000mV AC. Select CAL on main function switch. Connect PAT Earth Bond Clip to S/C I stud, operate PAT control. The short circuit current is measured, Range 0 to 2000mA AC. Connect PAT Earth Bond Clip to Earth Bond studs in turn (20, 50, 100, 200, 500, milliohms 1, 2, 4, 9, Ohms), operate PAT control and note PAT meter readings. Low Current DC Earth Bond for test currents of less than 2A Within the Earth Bond LOW CURRENT section of the PAT-Cal 2 Select O/C V on main function switch. Change the meter to read DC by pressing the AC/DC button ( ~ sign on the meter will be turned off). Connect PAT Earth Bond Clip to O/C V stud, operate PAT control and note PAT-Cal 2 meter reading. The open circuit voltage is measured, Range 0 to 2000mV DC. Select CAL on main function switch. Change the meter to read DC by pressing the AC/DC button ( ~ sign on the meter will be turned off). Connect PAT Earth Bond Clip to 100 milliohm stud, operate PAT control. The short circuit current is measured, Range 0 to 2000mA DC. Connect PAT Earth Bond Clip to Earth Bond studs in turn (100, 200, 500, milliohms 1, 2, 4, 9, Ohms), operate PAT control and note PAT meter readings.

12 Insulation Within the Insulation section of the PAT-Cal 2 Note: The Earth Bond Stud cover must be in place over all 10 studs to conduct this test. Select the Insulation function on the PAT, select O/C V on the main function switch. Operate the PAT. The open circuit voltage is displayed on the PAT-Cal2 meter, range 0 to 2000V DC. (Do not exceed 1000V max input limit). Select the Insulation function on the PAT, select CAL on the main function switch, select S/C on Insulation rotary switch. Operate the PAT. The short circuit current is displayed on the PAT-Cal2 meter, range 0 to 20 ma DC. Select the Insulation function on the PAT, select Insulation values in turn (100, 500 Kohms 1, 2, 4, 7, 10, 20, 50, 100 Mohms). Operate the PAT and note PAT meter readings.

13 Leakage Within the Leakage section of the PAT-Cal 2. Note: The Earth Bond Stud cover must be in place over all 10 studs to conduct this test. Select the Leakage function on the PAT, select O/C V on the main function switch. Operate the PAT. The open-circuit voltage is displayed on the PAT-Cal2 meter, range 0 to 2000V AC. (Do not exceed 1000V max input limit). Select the Leakage function on the PAT, select CAL on main function switch. Select the Leakage current values in turn (0.5,1, 2, 5, 10 and 15 ma). Operate the PAT and note actual leakage current on the PAT-Cal2 meter, range 0 to 20mA, and the indicated leakage current on the PAT.

14 4.4 Substitute Leakage 14 Some PATs carry out a Substitute Leakage test where the appliance leakage is measured at a low (20 50VAC) voltage and the result is scaled up to what the leakage current would be if full mains voltage were applied. To calibrate Substitute Leakage: Select the Substitute Leakage function on the PAT, select O/C V on the main function switch, select 1/10 range on the PAT-Cal2 meter. Operate the PAT and note the open-circuit voltage displayed on the PAT- Cal2 meter, range 0 to 200V AC. Select the Substitute Leakage function on the PAT, Select CAL on the main function switch. Select the Leakage current values in turn (0.5,1, 2, 5, 10 and 15 ma). Operate the PAT and note the substitute leakage current displayed on the PAT-Cal2 meter and the indicated leakage current on the PAT. Use the 1/10 range switch on the PAT-Cal2 meter where necessary to measure small currents. Calculate the full mains leakage current at nominal mains voltage and compare with that indicated by the PAT. Full mains leakage current Substitute leakage current (measured by PAT-Cal2 ) Substitute O/C V IL mains IL sub V sub IL mains = nominal mains voltage x IL sub V sub 4.5 Touch Leakage Note: The 13A plug on the PAT-Cal 2 must remain plugged into the PAT to provide an earth return path during this test. Within the Leakage section of the PAT-Cal 2, Select TOUCH LEAKAGE on main function switch. Connect the PAT touch leakage probe to the 4mm TOUCH LEAKAGE socket on PAT-Cal 2. Read the touch leakage current on the PAT-Cal2 meter and on the PAT under test. The touch leakage is supplied from a constant current source of approximately 1.9mA 50Hz AC and will drive a maximum of a 2K2 load. Note: The Function Switch must not be left in the Touch Leakage position as this will discharge the PAT-Cal2 battery.

15 Load Test An external load rated at up to 13A 240V (approx 3KW) may be connected to the 16A IEC External Load connector. This load may be switched on and off by the adjacent rocker switch. Select VOLTAGE on main function switch. The mains supply voltage is measured, Display Range 0 to 2000V AC. Select CURRENT on main function switch. The load current is measured, Display Range 0 to 20A AC.

16 Calibrating Insulation/Continuity Testers General Information Operation Insulation/Continuity Testers may be calibrated by utilising the PAT-Cal 2 s Insulation and Earth Bond functions. Most insulation testers have a choice of test voltages e.g. 100V, 250V, 500V and 1000V. Note: The PAT-Cal 2 is only suitable for use up to 1000V. Insert the PAT-Cal 2 plug into the 4mm - Test Lead Adapter. Connect the Insulation Tester leads to the appropriate 4mm sockets on the adapter as described below. Insulation Connect the insulation tester s leads, common (usually black) to the GREEN socket on the Adapter. Connect the high potential (usually red) to the RED socket on the Adapter. Within the Insulation section of the PAT-Cal 2 Select O/C V on the main function switch. Simultaneously operate the Insulation Tester and the ON /OFF rotary switch located between the Insulation and Leakage sections. If the Insulation Tester has a choice of test voltages, these should be calibrated in turn. Please note PAT-Cal 2 s upper limit of 1000V DC. Select CAL on main function switch. Select insulation values in turn (100K, 500K, 1M, 2M, 4M, 7M, 10M, 20M, 50M 100M ) on PAT-Cal 2. Simultaneously operate the Insulation Tester and the ON/OFF rotary switch located between the Insulation and Leakage sections. Note readings on the insulation tester. Readings should be taken for each of the test voltages available on the unit being calibrated. Low Value Continuity/Resistance Connect the Tester lead, common (usually black) to the GREEN socket on the Adapter. Within the Earth Bond section of the PAT-Cal 2 select CAL. Connect the high potential (usually red) to the PAT-Cal 2 s Earth Bond studs (using a suitable test clip) in turn and note the reading obtained.

17 17 POWER SUPPLY Internal Battery 6V NiCad Battery life >200 hrs between charges MECHANICAL High impact strength case Dimensions 405 x 330 x 177mm Weight 5Kg 5 SPECIFICATIONS ENVIRONMENTAL Temperature: Operating 10 to 30 o C, Storage -10 to 50 o C Humidity: Operating < 75% Altitude: Operating 0 3km, Non Operating 0 12km MEASUREMENTS Internal meter with 3,5 digit (1999 full scale) LCD,the meter may be switched from DC to AC or AC to DC if the default setting is incorrect for the test in progress. The meter may also be switched to 1/10 scale on most ranges if the reading is below 199. An alternative external measuring instrument may be connected to the 4mm EXT. METER sockets across which will be 200mV full scale for all ranges. EARTH BOND Calibrated low value resistive loads 20mR accuracy 5% 50mR accuracy 2% 100mR, 200mR, 500mR, 1, 2, 4, 9 R accuracy 1% Open circuit voltage measurement: range 0 20V accuracy 0.25% of full scale High current AC measurement: range 0 50A AC accuracy 0.5% of reading +/- 0.2A Low current AC measurement: range 0 2A AC accuracy 0.5% of reading +/- 2mA Low current DC measurement only valid for loads of 100mR and above range 0 2A DC accuracy 1% of reading +/- 2mA INSULATION Calibrated high value resistive loads 100K, 500K, 1M, 2M, 4M, 7M, 10M accuracy 0.1% 20M, 50M, 100M accuracy 1.0% Open circuit voltage measurement range 0 1kV DC, accuracy 0.25% of full scale Current measurement range 0 20mA DC accuracy 0.25% of full scale

18 18 LEAKAGE Resistive loads giving nominal leakage currents at 230V AC of 0.5, 1, 2, 5, 10, 15mA. Mains voltage measurement: range 0 500V AC accuracy 0.25% of full scale. Leakage current measurement: range 0 20mA AC accuracy 0.25% of full scale. TOUCH LEAKAGE A constant current source to calibrate touch leakage meters Current 1.9mA AC nominal. Current measurement: range 0 2mA AC accuracy 0.25% of full scale Frequency 50 +/-5 Hz Maximum load resistance 2K2. LOAD Provision to connect an external load via a 16A IEC connector. Mains voltage measurement: range 0 500V AC accuracy 0.25% of full scale. Load current measurement: range 0 13A AC accuracy 0.5% of full scale. INSULATION/CONTINUITY TESTERS An adapter is provided to allow 4mm test leads to be connected to the PAT-Cal 2.

19 Declaration of Conformance EC DECLARATION OF CONFORMITY We, Time Electronics Ltd Botany Industrial Estate Tonbridge Kent, TN9 1RH, UK Declare that the 5080 PatCal 2 Meets the intent of the EMC Directive 89/336/EEC and the Low Voltage Directive 73/23/ EEC. Compliance was demonstrated by conformance to the following specifications, which have been listed in the Official Journal of the European Communities. EMC BS EN 61326:1998 IEC 61326:1997 Safety BS EN :2001 IEC :2001 Cat II, Pollution Degree 1... QA Manager 17 th Sept 2001 V1.1

20 20 FAULT CHECK LIST If the unit does not function at all. Ensure that the PAT-Cal 2 has not gone into auto shutdown mode (15 minutes of inactivity). To reactivate, switch off then on again. Earth bond ranges show very low or no readings. The AC/DC selector switch is in the incorrect position. Insulation ranges do not work. Ensure the Earth Bond Stud cover is in the correct position. Ensure the function selector switch is in the correct position. Leakage ranges do not work. 6 FAULT DIAGNOSIS Ensure the Earth Bond Stud cover is in the correct position. Ensure the function selector switch is in the correct position.

21 21 7 GUARANTEE AND SERVICING RETURNING - GUARANTEE PERIOD The PAT-Cal2 is guaranteed against defects in materials and workmanship for a period of one year from its delivery to the customer. During this period, we will, subject to the instrument not being damaged due to maltreatment or overload, repair or replace it free of charge excluding shipping costs. For servicing under guarantee, the instrument type and serial number must always be quoted, together with details of any fault and the service required. The purchaser of the instrument must prepay all shipping charges. This guarantee is void if servicing or repair has been attempted by an unauthorised person or agent. SERVICE and RE-CALIBRATION After the guarantee period has expired we can still re-calibrate and service your instrument. Return it direct to Time Electronics or our authorised agent. Time Electronics can provide a fast turn-around for repair and recalibration. If a calibration certificate is required it should be specifically ordered and specified either NPL Traceable or UKAS (NAMAS).