Related Models

>Model 521/RA5 - ±20ppm to 1000Vdc

Model 522 - ±20ppm to 100Vdc

Model 523 - ±4ppm to 100Vdc
 

Features
“Limit Of Error” (or Worst Case) methods.
E Mode: ±(0.002% of setting + 0.0005% of range)
I Mode: ±(0.005% of setting + 1µA) compliance with variable control)
Accuracies based on one full year calibration cycle and conservatively specified by using the "Limit-Of-Error" (or worst case methods).
Magnitude is maintained during polarity changes, function changes and range changes in the manual mode. I.e., this eliminates the requirement of reentering the magnitude.
3 voltages selections (1ppm resolution or 6 decades):
±1000Vdc resolved to 1mV
±100Vdc resolved to 100µV
±10Vdc resolved to 10µV
±100mVdc resolved to 0.1µV
2 current selections:
±100mAdc resolved to 0.1µA
±10mAdc resolved to 0.01µA
(Note: 100Vdc com
Programming: Integrated microprocessor, GPIB interface. Local and remote control.
The control logic is microprocessor based.
True bipolar control with balanced zero.
A “crowbar” zero reference may be selected.
Floating Output: Optically isolated between analog output and digital input lines.
Traceability to the U.S. N.I.S.T.

Options
Extended 1 Year Warranty: Part No. EW521.

Certification: A Certificate of Compliance is issued with each new instrument to certify the calibration traceable to U.S. N.I.S.T. (INCLUDED).
 

APPLICATIONS
   Calibration of DVMs, DMM, meters, chart recorders, A/D converters, ATE, monitors, controllers, logging
   systems, etc.

   Linearity check of amplifiers and function modules.

   Simulation of thermocouples and strain gages.(4mA to 20mA and 10mA to 50mA) + other transducers.
   Note: Compliance voltage up to 100Vdc.

Imbedded Standard for ATE and Data Logging Systems.

SPECIFICATIONS

VOLTAGE MODE

Crowbar – Indicates selected/programmed short of terminals.

Accuracy:
(Relative to N.I.S.T. Standards) The Accuracy statement is based on the “Limit-of-Error” (or “worst-case”) method. All other specifications noted hereafter, which affect accuracy, e.g., line, load, temperature*, drift changes are included in the accuracy statement. Thus, all other specifications are listed as *non-Additive and are indicated * below.

±(0.002% of setting + 0.0005% of range + 3µV)

1000Vdc Range: ±(0.004% of setting + 0.001% of range)

Note: The “+3µV” specified above applies primarily to the 100mV range where measurements at these low levels should be stated conservatively. It become insignificant on the higher ranges. Notice: The accuracy statement above, based on the “Limit of Error” method is VALID FOR ONE YEAR calibration cycles.

Stability (*non-additive): 8 hrs, ±0.00075%; 24 hrs, ±0.001%;90 days, ±0.0015%; 1 year, ±0.002%.
Line And Load Regulation: ±0.0005% from no load to full load and/or for a 10% line fluctuation.
 

CURRENT MODE

Accuracy: (See definitions under voltage mode) ±[0.005% of setting + 1µA].
Stability (*non-additive): 8 hrs, ±0.001%; 90 days, ±0.0015%;1 year, ±0.002%.
Line & Load Regulation (*non-additive): ±0.0005% for a 10% line fluctuation and from short-circuit to full compliance.

PROGRAMMING
Remote Programming is included. It conforms to the IEEE-488.1 convention, designated GPIB and is classified as a “Listener” and a “Limited Talker”.
The selected bus address is announced on the front panel display at initialization of the instrument.

Local/Remote Mode is controlled by the operator not the control device. i.e., computer, µP, etc. If the 521 is addressed in “local” the flag response will indicate a “device-not-present” status. Bus address is set in binary codes on a 5 dip-switch located on the rear panel. Programs written for older series of the 521 as well as the 520 and 501 are compatible with this latest instrument.

Local Mode: Local control is easily established, by the operator, via a front panel switch. (The instrument does not have to be powered-off to establish local control).

The front panel controls duplicate all the programmable functions:

     polarity/zero
     magnitude in 6 decades
     range/function

GENERAL
Isolation: Power transformer to analog output, 2.5 ´ 104M ohms, 300pF; Control logic to analog output, optically isolated; 109 ohms, 130pF, 500Vdc.
Temperature Coefficient: Ambient, ±0.0005%/°C; operating limit, ±0.001%/°C.
Switching & Settling Times: Step changes, 5 milliseconds; range changes, 300 milliseconds.
Protection: Voltage mode, Short-circuit and overload protection; current mode, open-circuit protection; front panel enunciator will indicate malfunction condition; recovery is automatic.
Warm-up Time: 2 hours.
Mounting: Rack mounting facilities standard 19 inches; 482.6mm and for bench use with convenient (and removable) tilt bale. (INCLUDED).

MECHANICAL
Power Requirements: 50 watts; 115V or 220Vac ±10%; 50Hz/60Hz.
Temperature:
   Calibration, 23°C ± 1°C
   Ambient (limit-of-error), 20°C to 30°C
   Operating Limit, –10°C to 50°C
   Storage, –40°C to 85°C.
Dimensions: 19" (48.3cm) wide, 3.5" (8.9cm) high, 18" (45.8cm) deep.
Weight: 14.7 lbs (6.7kg) net; 23 lbs (10.5kg) shipping.

TERMINALS
Output Terminals are mounted on the front and rear panels in the following configurations:

Rear Panel Mounted Output Connector must be used for rated output performance.
This is a MIL Spec connector providing connections for high and low output, sensing (four terminal output) and case ground. A pair of binding posts are installed for 1000Vdc range, when the Option RA-5 is ordered.
Front panel mounted outputs are available for monitoring.
Program (digital) Connector mounted on the rear panel conforms to the specifications of the GPIB (1978).

OPTIONS
Auxiliary Instrument Model PCS-2B: Programmable 10 Ampere Current Calibrator. This is a “building block” chassis which operates in conjunction with the Model 521/RA5.
Lab Windows and Lab View drivers are available for direct downloading from National Instruments at www.natinst.com.
Note: Drivers for Krohn-Hite Models 521/RA5 and 522 are listed under “520A”.

OPTIONAL ACCESSORIES
CAB-005: Cable, Two Conductor Shielded Balance Line
CAB-018: Cable, Multi-stacking Double Banana plug
CAB-023: Cable Set, Low Thermal EMF Retractable Banana
CAB-024: Cable Set, Low Thermal EMF Spade Lug

WARRANTY
Full ONE YEAR warranty on parts and labor and a full ONE YEAR warranty on specifications and performance.
Extended 1 Year Warranty: Part No. EW521.
Certification: A Certificate of Compliance is issued with each new instrument to certify the calibration traceable to U.S. N.I.S.T. (INCLUDED).

Specifications and prices are subject to change without notice.

* The limit-of-error applies over the standard ambient operating temperature.