Performance That Conquers Any Resistance
4300C Programmable Digital Micro-Ohmmeter
Features of the 4300C include four terminal compensation, a very low 2mΩ range, selectable test current levels (up to 10 amps), a fast-settling charge inductor mode, safety disconnect status indicators, automatic temperature compensation, a basic accuracy of ±0.03% and a push button or GPIB controlled current on/off selector.
- User-selectable test-current up to 10A
- Boosted compliance voltage mode for rapid charging of motors and transformers
- “Safe to Disconnect” status indicators
- Test-current “On/Off” switch
- Selectable voltage sensitivity – 1μV, 10μV, 100μV
- 18 voltage sense/current combination provide optimal measurement conditions
- Selectable display refresh (100ms-to-500ms) with variable intensity
- RS-232 serial interface
- Programmable-automatic temperature compensation
- Built-in limit comparator with visual-acoustic indications and rear panel relay terminals
- Run/Hold w/Peak Detector
- Print/Log Function
Transformers, Motors, Cables, and More
The 4300C is the perfect instrument for tackling ultra-low resistance testing requirements associated with motors, transformers, fuses, connectors, breakers, bonding/weld resistance, and many other applications. For rapid testing of inductive loads the 4300C’s charge inductor mode provides in excess of 20V compliance. This model reduces the settling time by a factor of 5:1 on inductive loads. The result is valid readings in minutes instead of hours when testing 400MW utility transformers. A solid-state “Crowbar” design provides front-end protection for up to 500 amps of induced current.
Automatic Temperature Compensation
Copper and aluminum will exhibit approximately a 0.4% change in resistance for a 1°C change in ambient temperature. When in Automatic Temperature Compensation mode (TCM), the Valhalla 4300C temperature sensor automatically senses the ambient temperature and references the resistance value of the test item equivalent to being in a 20° C controlled environment. A 10° C change in ambient (i.e. open air, shop floor) provides a 4% change in the resistance of a copper item. Without this “TCM” feature, a micro-ohmmeter which may be 0.02% accurate may be making a 5-10% resistance measurement error when measuring copper or aluminum (i.e., transformer wire) material.
Virtually all competitive micro-ohmmeters lack copper or aluminum (TCM) ambient temperature coefficient of resistivity compensation. Ambient temperature can have drastic effect on the resistivity of a conductor. Without temperature compensation, materials can easily be erroneously classified during the resistance testing process. Correcting the resistance measurement on copper conductors, while ambient temperature varies makes “TCM” a very useful feature.
Large Inductor Resistance Measurement
The 4300C’s 10A current source is ideal for low resistance inductors such as utility transformers. Combining the current output with boosted compliance voltage (>20 VDC) enables rapid stable resistance readings in seconds, not hours. Having unique features like Automatic Temperature Compensation, High Level Current Sourcing (10A) with High Compliance Drive circuitry and 18 combinations of Voltage / Current Range Selectivity, the 4300C Digital Micro-ohmmeter is second to none.
Charging Inductor Mode Indicator
The Valhalla 4300C charging inductor mode LED, indicates when the unit’s current source compliance voltage is exceeded. The 4300C “Boost Mode” then increases the compliance voltage to exceed 20V output to reduce the settling time (charges the inductance) when inductive loads (i.e. large transformers) are being measured.
TCM Mode Accuracy
|1||2mΩ||20mV||2.0000mΩ||100nΩ||10A||± .06 ± .0006m||±50ppm/°C||± .11 ± .0006m|
|2||20mΩ||20mV||20.000mΩ||1µΩ||1A||± .04 ± .006m||±50ppm/°C||± .09 ± .006m|
|3||200mΩ||20mV||200.00mΩ||10µΩ||0.1A||± .04 ± .06m||±50ppm/°C||± .09 ± .06m|
|4||2Ω||20mV||2.0000Ω||100µΩ||10mA||± .04 ± .0006||±50ppm/°C||± .09 ± .0006|
|5||20Ω||20mV||20.000Ω||1mΩ||1mA||± .04 ± .006||±50ppm/°C||± .09 ± .006|
|6||200Ω||20mV||200.00Ω||10mΩ||0.1mA||± .04 ± .06||±50ppm/°C||± .09 ± .06|
|7||20mΩ||200mV||20.000mΩ||1µΩ||10A||± .06 ± .003m||±50ppm/°C||± .11 ± .003m|
|8||200mΩ||200mV||200.00mΩ||10µΩ||1A||± .04 ± .03m||±50ppm/°C||± .09 ± .03m|
|9||2Ω||200mV||2.0000Ω||100µΩ||0.1A||± .04 ± .0003||±50ppm/°C||± .09 ± .0003|
|10||20Ω||200mV||20.000Ω||1mΩ||10mA||± .04 ± .003||±50ppm/°C||± .09 ± .003|
|11||200Ω||200mV||200.00Ω||10mΩ||1mA||± .04 ± .03||±50ppm/°C||± .09 ± .03|
|12||2kΩ||200mV||2.0000kΩ||100mΩ||0.1mA||± .04 ± .0003k||±50ppm/°C||± .09 ± .0003k|
|13||200mΩ||2V||200.00mΩ||10µΩ||10A||± .06 ± .03m||±50ppm/°C||± .11 ± .03m|
|14||2Ω||2V||2.0000Ω||100µΩ||1A||± .04 ± .0003||±50ppm/°C||± .09 ± .0003|
|15||20Ω||2V||20.000Ω||1mΩ||0.1A||± .04 ± .003||±50ppm/°C||± .09 ± .003|
|16||200Ω||2V||200.00Ω||10mΩ||10mA||± .04 ± .03||±50ppm/°C||± .09 ± .03|
|17||2kΩ||2V||2.0000kΩ||100mΩ||1mA||± .04 ± .0003k||±50ppm/°C||± .09 ± .0003k|
|18||20kΩ||2V||20.000kΩ||1Ω||0.1mA||± .04 ± .003k||±50ppm/°C||± .09 ± .003k|
The Model 4300C can also be programmed for Hi-Lo limit comparison. Three front panel LEDs allow a visual of the result and a rear panel relay closure screw terminal block can be used to implement an automated batch sorting system for components or products, operate counters, sound alarms or shut off a process. A Run/Hold function is also a standard feature of the 4300C. The user can program this function as a peak hi or peak low detector. Measurements may be printed or logged and viewed in a spread sheet by using the Print/Log feature also standard with the Model 4300C.