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HARS-LX Series

Maintenance

Switch Position

Potentiometer Designation

All decades but 1 k

Ω

Potentiometer Designation

1 k

Ω

decade

T10

T10 (1 M steps only)

Table 5-1: Trimming Potentiometers

Figure 5-1: Typical Trimmer Board

Trim

Potenti-
ometers

Содержание HARS-LX

Страница 1: ...ietlabs com TEL 516 334 5959 FAX 516 334 5988 www ietlabs com IET LABS INC HARS LX Laboratory Standard Decade Resistance Substituter User and Service Manual Copyright 2014 IET Labs Inc Visit www ietla...

Страница 2: ...PRECISION INSTRUMENTS FOR TEST AND MEASUREMENT Email info ietlabs com TEL 516 334 5959 FAX 516 334 5988 www ietlabs com IET LABS INC...

Страница 3: ...t no charge when returned to IET Changes in this product not approved by IET or application of voltages or currents greater than those allowed by the specifications shall void this warranty IET shall...

Страница 4: ...USED TAKE ALL MEASURES TO AVOID ACCIDENTAL CONTACT WITH ANY LIVE COMPONENTS USE MAXIMUM INSULATION AND MINIMIZE THE USE OF BARE CONDUCTORS WHEN USING THIS INSTRUMENT Use extreme caution when working w...

Страница 5: ...1 Thermal emf Considerations 5 4 4 Dial Setting 6 4 5 Power Considerations 6 4 6 Environmental Conditions 6 4 7 Switch Conditioning 6 4 8 Meter Shunt Applications 7 4 9 Kelvin Bridge Applications 7 C...

Страница 6: ...tituter 1 Figure 2 1 Typical Operating Guide Affixed to Unit 3 Figure 4 1 Kelvin Bridge Connections 7 Table 5 1 Trimming Potentiometers 11 Figure 5 1 Typical Trimmer Board 11 Table 5 2 Replaceable Par...

Страница 7: ...y feature solid silver alloy contacts and quadruple leaf silver alloy wipers which keep switch contact resis tance to under 1 m per decade and more impor tantly keep switch contact resistance reproduc...

Страница 8: ...ermetically sealed low inductance Terminals Four 5 way gold plated tellutium copperbinding posts with low thermal emf and low resistance for four terminal Kelvin measurements plus one binding post con...

Страница 9: ...00 1 211 0 M 4 100 100 HARS LX 4 1k 12 110 M 4 1 k 1 k HARS LX 4 10k 121 10 M 4 10 k none HARS LX 5 0 001 121 110 5 1 m HARS LX 5 0 01 1 111 10 k 5 10 m 10 m HARS LX 5 0 1 11 111 0 k 5 100 m 100 m HAR...

Страница 10: ...100 short term average value Environmental Conditions Operating Temperature 0 C to 55 C Storage Temperature 40 C to 70 C Switch Type Multiple solid silver contacts dust tight diallyl phthalate body To...

Страница 11: ...tandard temperatures near 23 C 3 3 Repackaging for Shipment If the instrument is to be returned to IET Labs contact the Service Department at the number or address shown on the front cover of this man...

Страница 12: ...low resistance increments are important care must be taken in connecting to the terminals of the decade box In particular to keep contact resistance to a mini mum 4 terminal connections should be empl...

Страница 13: ...0 Since the highest decade has an additional 11 po sition resistance values of over 1 2 times nominal maximum value can be obtained 4 5 Power Considerations To maintain the maximum possible accuracy a...

Страница 14: ...resistance standard for all Kelvin bridge measurements When connected as shown in Figure 4 1 errors caused by lead and contact resis tances can be made negligible because they appear as part of the ge...

Страница 15: ...igure 4 1 Figure 4 1 Rheostat Dial In order to eliminate contact resistance and thermal emf the HARS LX integrates the rheostat as shown in Figure 4 2 This way the wiper is in the low potential circui...

Страница 16: ...from the side of the instrument and remove the housing 2 Remove any dust or debris using optical grade dry compressed air or a clean brush 3 Replace the housing and reattach the 4 hous ing screws The...

Страница 17: ...he follow ing models HATS LR HATS Y SRL Series The 1 and 10 transfer standards are optional and are only used to take advan tage if desired of the adjustability of these two decades Precision resistan...

Страница 18: ...trim or adjust any resistances proceed as follows 1 Stabilize HARS LX at laboratory tempera ture of 23 C for at least 8 hours 2 Remove the 4 housing screws from the sides of the instrument and remove...

Страница 19: ...Designation All decades but 1 k Potentiometer Designation 1 k decade 1 T0 T1 2 T1 T2 3 T2 T3 4 T3 T4 5 T4 T5 6 T5 T6 7 T6 T7 8 T7 T8 9 T8 T9 10 T9 T10 11 T10 1 M steps only Table 5 1 Trimming Potenti...

Страница 20: ...y Not Shown HARS 4000 LX 0 1 100 m step Decade Switch Assembly Not Shown HARS 4000 LX 1 1 step Decade Switch Assembly Not Shown HARS 4000 LX 10 10 step Decade Switch Assembly Not Shown HARS 4000 LX 10...

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