About this Manual - Simpson 260

1 2 About this ManualTo the best of our knowledge and at the time written, the information con-tained in this document is technically correct and the procedures accurateand adequate to operate this instrument in compliance with its original ad-vertised and Safety InformationThis Operator s Manual contains warning symbols which alert the user tocheck for hazardous conditions. These appear throughout this Manual whereapplicable, and are defined below. To ensure the safety of operating perfor-mance of this instrument, these instructions must be adhered to.

2 !Warning, refer to accompanying , risk of electric instrument is designed to prevent accidental shock to the operator whenproperly used. However, no engineering design can render safe an instru-ment which is used carelessly. Therefore, this Manual must be read carefullyand completely before making any measurements. Failure to follow direc-tions can result in a serious or fatal accident.!Technical AssistanceSIMPSON ELECTRIC COMPANY offers assistance Monday through Friday7:30 am to 5:00 pm Central Time.

3 To receive assistance contact TechnicalSupport or Customer Service at (847) : and ReturnsSIMPSON ELECTRIC COMPANY warrants each instrument and other articlesmanufactured by it to be free from defects in material and workmanship un-der normal use and service, its obligation under this warranty being limited tomaking good at its factory or other article of equipment which shall within one(1) year after delivery of such instrument or other article of equipment to theoriginal purchaser be returned intact to it, or to one of its authorized servicecenters, with transportation charges prepaid, and which its examination shalldisclose to its satisfaction to have been thus defective.

4 this warranty beingexpressly in lieu of all other warranties expressed or implied and of all otherobligations or liabilities on its part, and Simpson ELECTRIC COMPANY nei-ther assumes nor authorizes any other persons to assume for it any otherliability in connection with the sales of its warranty shall not apply to any instrument or other article of equipmentwhich shall have been repaired or altered outside the Simpson ELECTRICCOMPANY factory or authorized service centers, nor which has been subjectto misuse, negligence or accident, incorrect wiring by others, or installationor use not in accord with instructions furnished by the Instrument is designed to prevent accidental shock to the operator whenproperly used.

5 However, no engineering design can render safe an instru-ment which is used carelessly. Therefore, this Manual must be read carefullyand completely before making any measurements. Failure to follow direc-tions can result in serious or fatal HAZARD: As defined in IEC-1010-1 Safety Requirements for Elec-trical Measurement, Control and Laboratory Use, a shock hazard shall beconsidered to exist at any part involving a potential in excess of 30 volts rms(sine wave) or volts DC or peak and where a leakage current from thatpart to ground exceeds MIU (Measure Indication Units) when measuredwith an appropriate measurement instrument as defined in Section A of.

6 UL-1244 calls for the same voltage and measurement limits as IEC-1010-1:1990 but UL-1244 specifies a slightly different test network. SimpsonElectric manufactures test equipment to measure shock hazard as set forthby both specifications. The Simpson Model 228 uses the networks specifiedby IEC-1010-1 and is suitable for measuring shock hazard as defined in thatdocument. The Simpson 229-2 uses the measurement networks specified inUL-1244 and is suitable for measuring shock hazard as defined in And Accessories.

7 Data Specifications .. 52. And Inspection .. Source Requirements .. to Position Instrument While Operating .. 73. CONTROLS, CONNECTORS & Panel Description .. 7 4. Precautions .. Instructions .. Measurement Measurement Settable Continuity .. 105. THEORY OF Of Measurement .. 116. OPERATOR Removal .. Replacement .. Simpson 444 Micro-Ohmmeter measures resistances from 1 micro-ohmto 20 ohms. It measures by using a small test voltage (100 microvolt maxi-mum) and a 4 wire measurement technique.

8 The measured resistance is dis-played on 4-1/2 digit LCD display. The 444 is designed to be run from thepower line, but self-contained rechargeable Ni-Cad batteries are providedfor field Simpson 444 has two measurement modes, an automatic AC measure-ment mode and a Manual DC measurement mode. In the AC mode a 100microvolt maximum square wave is used to test the resistance. Because ofthe AC nature of the square wave, all offset voltages and thermocouple ef-fects are automatically canceled and the resistance can be directly read.

9 Inthe DC mode, a 100 microvolt maximum DC test voltage is used and the usermust manually cancel out any offsets and thermocouple And AccessoriesAll items and accessories required for the operation of the 444 are furnishedwith each Instrument, and listed in Table ConsiderationsThis Operator s Manual contains cautions and warnings alerting the user tohazardous operating and servicing conditions. this information is flagged byCAUTION or WARNING symbols throughout this publication, where appli-cable, and is defined on the inside front cover of this Manual under SAFETYSYMBOLS.

10 To ensure the safety of operating and servicing personnel and toretain the operating conditions of this Instrument, please adhere to these Data SpecificationsTable 1-1 lists the technical data for the 444 Digital 1-1. Technical DataThe following specifications apply over an operating temperature range of18 to 28 C and at a relative humidity up to 80% unless otherwise :AC MODE: ( of input + 15 counts)DC MODE: ( of input + 600 counts) Test Voltage:100 V (Peak) Techniques:Pulse (AC)40 Hertz Square WaveDCSwitchable :Resistance below setpoint activates audiblebeeper and display annunciator.