53A-522 – Digital Multimeter Card
OPT 1V – Add VXIbus Compatibility
53A-780 – Hooded Connector

• Fully programmable 4 1/2 digit guarded, dual slope integrating system multimeter
• Self-calibrating
• 1 µV dc sensitivity with 115 dB common mode rejection
• 15 readings per second
• AC, DC, 2-wire or 4-wire Ohms
• Buffer storage capability (333 measurements)

The DMM Card is a 4 1/2 digit, 15 readings per second, guarded, dual slope integrating system multimeter with four programmable measurement functions: DC voltage, True-RMS, AC voltage, and 2 or 4 wire Ohms. The DMM has µV DC sensitivity and requires no potentiometer or trimmer adjustments for calibration.

Electronic calibration is accomplished by storing offset and gain factors for each DMM range and function in EEPROM (Electrically Erasable Programmable ROM). The DMM is calibrated by applying a known calibration voltage or resistance and instructing the Card to perform an automatic calibration.

Signals to be measured can be routed directly to the DMM Card front edge connector or from 53A-331 Reed Relay Scanner Cards via the 53A System backplane.

A column of twelve LEDs provides Built-in-Test Equipment (“BITE”) for the DMM Card.  Individual LEDs indicate the function and range programmed, while an error LED indicates that an incorrect command has been sent to the Card.


Input Resistance:
10 MOhms ±0.5%.

Normal Mode Rejection:
73 dB @ 50/60Hz ±0.1%.

Effective Common Mode Rejection
(1 KOhm unbalance):
125 dB@ 50/60 Hz ±0.1%,
115 dB@ DC.

Temperature Coefficient:
±(.008% of reading + 0.9 counts)/°C on 200 mV and 20V ranges.
±(.008% of reading+ 0.6 counts)/°C on all other ranges.

Crest Factor:
1:2 for specified accuracy.
1:3 for additional 0.1% error.
1:7 for additional 1% error.


0.01 Ohm on 200 Ohm range.

Accuracy (1 yr at 23°C):
±(.08% of reading +3 counts) on 2 KOhm through 200 KOhm ranges.
±(.14% of reading +3 counts) on 2 MOhm and 200 Ohm ranges.
±(.98% of reading +3 counts) on 20 MOhm range.

± (.007% of reading + 0.05 counts)/°C on low ranges.
±(.014% of reading + 0.05 counts)/°C on 2 MOhm range.
±(.077% of reading + 0.05 counts)/°C on 20 MOhm range.


Function Selection:
Programmable, DC, TRUE RMS AC. 2-or 4-wire Ohms.

Range Selection:
Programmable, fixed range or autorange.

Maximum Input:
±700V dc or ac RMS.

Type Input
Floating, guarded ±300V dc common-to-ground, ±200V dc common-to-guard.

Maximum Reading Rate
(Auto range Off):
15 readings/second (maximum power line rejection at 60 Hz).
12.5 readings/second (maximum power line rejection at 50 Hz).

Programmable trigger command, auto trigger (DMM is automatically triggered each time a reading is requested) or external TTL input.

Calibration Cycle:
1 year.

Programmed By:
ASCII Characters.

Recommended Cable:

Available Option:
OPT 1V, add VXIbus compatibility.

Note: Each count equals the value of one bit in the selected range.