Valhalla 2555A Precision AC-DC 100AMP Current Calibrator Features Include:
• Up to 20 Amps/phase direct (self contained shunt 0.1%)
• Precision AC/DC Transconductance Amplifier
• Programmable AC~DC 100Amp Current Calibrator/Current Source
• Calibration Traceable to NIST
• Maximum Output Current: 100A DC or RMS AC
• Highly Accurate
• Ultra-low Noise
• Ultra-Stable
• Excellent Response time
• High CMR
• Load Regulation: Output current Δ < ± .002%
• Dynamic Range: 0 to 100% of range up to maximum rated output (100A max.)

The 2555A is the world's leading 100 Ampere AC-DC Current Standard. The 2555A has earned this position through 30 years of proven rock-solid reliability and unmatched performance. Our discriminating customers include the U.S. Army, Navy, Air Force and the National Institute of Standards and Technology as well as an impressive list of hundreds of other satisfied 2555A owners around the world that reads like the Who's Who of metrology.

Capable of delivering from 1mA to 100 amps DC or RMS AC of precise constant current, the 2555A is ideal for direct calibration of ammeters, wattmeters, DMM's, shunts, current transformers and Hall effect devices. The superb stability of Valhalla's patented transconductance amplifier* technology allows the 2555A to be used for transfer measurements on .001 ohm primary resistance standards. Applications for the 2555A outside of the field of metrology include component testing on fuses, circuit breakers, relays and high current connectors.

The 2555A supplies four volts of compliance in order to drive heavy burden loads and still delivers constant current. The output compliance is continually monitored by the unit's internal voltmeter. Compliance status is displayed at all times on the 2555A's compliance indicators. To insure that the compliance voltage is available to drive the load (and not the leads), Valhalla offers two heavy duty six foot 100 amp cable sets. The "HMF" set is terminated in 2" opening, 500 amp rated, injection molded clamps, while the "HC" version is terminated in no. 4 copper ring lugs.

*Protected Under U.S. Patent No. 409133

he Valhalla 2555A is the "workhorse" in the metrology lab for the calibration of current shunts, ammeters, clamp-on meters, current transformers, and even low value resistance standards. The metrology lab isn't the only place a Valhalla 2555A comes in useful. Production departments and Quality Control test areas using the Valhalla 2555A can also benefit. Many companies improve their product reliability by using the 2555A for the screening of fuses, relays, circuit breakers, and a multitude of current sensor incorporated devices.

• Dynamic Range: 0 to 200% of range up to maximum rated output
• Maximum Output Current: 100A DC or RMS AC
• DC Accuracy: (180 days 25°C ± 5°C) all ranges <100A ±0.015% of range ±0.03% of output 100 Amp Range: ± .03% of range ±0.03% of output
• AC Accuracy: (180 days)( 25°C ± 5°C) ±0.15% of range ± 0.1% of output to 100Hz ±0.2% of range ± 0.2% of output to 400Hz ±0.3% of output ± 0.3% of range to 1KHz
• Input Impedance: 100 Kilohms
• Input/Output Ratio: 2.00000 volt input provides full scale output (1.0000 volt input produces 100.0 amps output)
• Stability: ±0.0005% - 15 min. (±0.005% for 24 Hours)
• Maximum Input: 3 VDC or 2 VAC (RMS)
• Response Time: 1 millisecond to ±0.01% of final value following input amplitude or frequency change
• Maximum Isolation Voltage: ± 200 VDC or Peak AC
• Input Common Mode Rejection Ratio: 60db @ DC linearly decreasing to 40 db @ maximum frequency
• Load Regulation: Output current changes less than ± .002%
• Temperature Range: 0°C to 50°C
• Temperature Coefficient: ±0.001% of output ±0.002% of range/°C below 20°C and above 30°C (double above for temperature coefficient for AC)
• Compliance Voltage: 4 Volts
• Size: 266mm/10" L x 432mm/ 17" W x 584mm/23" D
• Weight: 45 Kg/100 lbs. Net 66 Kg/140 lbs. shipping wt.
• Power: 115/230 VAC ± 10% 50-60Hz 2000 watts