MODEL 6242B
Automated Resistance Bridge
• Range: 0.001 to 100MΩ
• Linearity: 0.01 ppm of FS
• Resolution: 0.001 ppm of FS
• Best Accuracy: <0.1 ppm
• Maximum Ratio: 100:1
• DC Current Comparator Technology
• 7” Touch Screen display
MODEL INFORMATION
MI is the original manufacturer of the
Automated Direct Current Comparator (DCC)
Resistance Bridge, with the first commercial
automated bridge sold in 1991. Since then,
our bridges have been used in nearly every
NMI around the world for thier superior speed
and low uncertainties.
The 6242B Automated Resistance Bridge is
based on the same Direct Current Comparator
technology as found in the 6010 bridge
used by major laboratories to maintain their
primary standards. Therefore, it has most
of the same features that metrologists have
come to expect in an MI bridge. The 6242B
is ideal for those laboratories involved in
resistance and temperature measurements
that do not require the accuracy level of a
national laboratory. It was originally designed
as an automated, direct replacement for the
ESI 242() resistance measurement system.
The 6242B features include a new 7”
touch screen LCD display, four terminal
measurements up to 100 kΩ and two
terminal measurements to 100 MΩ,
automatic current reversal to eliminate
thermal EMF’s and a built-in self-calibration
routine to verify the linearity of the
comparator. The 6242B comes equiped with
a standard IEEE488 interface and two input
channels. The number of input channels can
be increased to a maximum of 40 by adding
two Models 4220A, 20-channel low thermal
matrix scanners. A Model 4220-1R SR
Series Hamon Adapter can also be added to
form a complete “turn-key” system capable
of automating calibrations for resistors and
ESI SR1010 & SR1060 transfer standards.
Precision DC Range Extenders can be added
to increase the measurement range of the
bridge to extend the range to 1 µΩ at up to
2,000 amps and higher.
Operation:
System Software:
The 6242B offers resistance ratio measurements at 1:10,
1:1, 10:1 & 100:1 ratio. This means for instance that
with a 1 Ω resistor on Rs you can measure a resistor on
the Rx(unknown) side anywhere from 100 mΩ to 100 Ω.
A very comprehensive and flexible Windows® based
software package is also available. It offers the features
that metrologists expect such as the ability to perform
automatic data acquisition, real time uncertainty
analysis, graphing, history logging and regression
analysis, and temperature calibrations, now and in the
future.
The touch screen display offers views of settings,
measeurement data, and graphing.
Temperature measurements may be performed easily
for measurement of SPRT’s with accuracy better than
0.1 mK.
System Requirements:
A computer is required to operate the 6242B-SW
running Windows XP or Vista and an IEEE488 Interface
Card (not included).
Calibration:
All bridges are shipped with a traceable calibration
report. As an option, an accredited calibration report can
be supplied. Measurements International is accredited
to 17025 in resistance ratio for 1:1 and 10:1 ratios from
0.1 Ω to 100 MΩ. Main Menu
System & Rack Settings
Program Selection
History Information
Low Resistance:
With the addition of range extenders, the model
6242B has the capability of extending the current
range to 2000A and the ratio to 1,000,000:1. You
can measure a 1 µΩ resistor against a Thomas-Type
or MI-Type 1 Ω standard resistor.
Specifications:
Resistance Range
6242B-100A model shown
100µΩ to 1 mΩ
1 mΩ to 10 mΩ
10 mΩ to 100 mΩ
100 mΩ to 1 Ω
1 Ω to 10 Ω
10 Ω to 100 Ω
100 Ω to 1 kΩ
1 kΩ to 10 kΩ
10 kΩ to 100 kΩ
100 kΩ to 1 MΩ
1 MΩ to 10 MΩ
10MΩ to 100MΩ
Accuracy With Range
(ppm)
Extender
N/A
<0.5
< 5.0
<0.5
<0.5
<0.5
<0.2
<0.1
<0.1
<0.1
<0.1
<0.2
<0.5
<2.0
<10.0
Specifications Cont’d:
Resistance Ratio Range
.001:1, .01:1, 0.1:1, 1:1, 1:10, 10:1, 100:1
Linearity
±0.01 ppm
Resolution
± 0.001 ppm of full scale
Input Channels
2 (expandable to 40 with 4220A Matrix Scanner)
Configuration
2 & 4 Terminal Measurements
Test Current Range
1μ to 150mA
Extended Test Current Option
150mA to 2000 Amps
Test Voltage Range
1 to 100V
Current Reversal
4 to 1000 Seconds
Time to Stated Accuracy (warm-up)
< 1 Minute
Temperature Coefficient
±0.02 ppm/°C
Mode of Operation
Manual or Automatic (IEEE488)
Operating Environment
18 to 34°C, 10 to 80% RH
Operating Power (Selectable)
100, 120, 220, 240V - 50/60Hz
Warranty
2 Year Parts & Labor
Accessories:
4220A Low Thermal Matrix Scanner
4220-1R Hamon Adapter
6511C 5 Amp Range Extender with
DC Supply
6011C 100 Amp Range Extender
6100A 100 Amp DC Current Source
6012M 2000 Amp Range Extender
6013M 400 Amp Range Extender
6242B Software & IEEE Interface
Items of interest: Standard Resistors, Equipment Racks, Interconnecting Wire, Resistor Oil and
Air Baths
Form MI 66, Rev. 6, Dated 09-03-03 (QAP19, App. “N”)
© Copyright 2009 Measurements International
Limited. All rights reserved.
Data Subject to Change- Rev 1, 5/09