[Amps] Resistandard Standard

[Will Matney]

All,

For any who may be interested, the same guy I bought the LCR meter off of has several ESI 230B guarded resistance bridges for sale at a good price. These are easily converted to a very accurate resistance standard which would sell for several hundred dollars. ESI actually makes one similar. One leg of the bridge contains all the precision resistors you need. What you do is put them in series with a DMM or Analog meter you want to test to set a meter. Not very much re-wiring is needed. He provides a good blown up schematic of the bridge on the auction page. There is also an internal DecaStat which is a precision 5 step potentiometer in another leg which you want to use in series with the fixed resistors, or you can use it by itself. This bridge/standard comes in handy for making precision resistors to use in metering circuits in amps. You can compare the resistors your going to use with the standard, or set a pot to a precision resistance to feed the meters. You can also use this without the modification as it but you need the rest of the equipment it goes with that has the voltage source and the meter. I bought one of these myself to do the conversion on and have a precision resistance standard.

Specs:

Resistance Range: 11 ranges, 1.2 Ogm to 12 GigaOhm full scale

Resolutions: Better than 1ppm of full scale on any range (1 microOgm per dial division on lowest range)

Accuracy: +/- 0.01% of reading or +/- 1 dial division, whichever is greater, when connected for short-circuit resistance.

Power Input: 1 Watt continuous, max.

http://cgi.ebay.com/ESI-230B-Guarded-Resistance-Bridge-1-Ohm-12-Giga-Ohm_W0QQitemZ7609246436QQcategoryZ25399QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Item number: 7609246436

Best,

Will