Custom-Cal has a high success rate in repairing both high accuracy and bench multimeters. Additionally we offer economically priced calibration utilizing standards like Fluke 5520 and Datron 4708. We specialize in quick turnaround times and we can handle expedited deliveries upon request.
The Agilent / HP 34401A digital multimeter has 6 1⁄2 digits of resolution, 1000 readings per second, and 15 ppm basic dc accuracy. HP-IB and RS-232 are standard with the ability to store up to 512 readings in internal memory.

Errors reported by 34401A:
  User Manual PDF
  Execution Errors
501 Isolator UART framing error
502 Isolator UART overrun error
511 RS-232 framing error
512 RS-232 overrun error
513 RS-232 parity error
514 Command allowed only with RS-232
  There are three commands which are only allowed with the RS-232 interface: SYSTem:LOCal, SYSTem:REMote, and SYSTem:RWLock.
521 Input buffer overflow
522 Output buffer overflow
531 Insufficient memory
  There is not enough memory to store the requested number of readings in internal memory using the INITiate command. The product of the sample count (SAMPle:COUNt) and the trigger count (TRIGger:COUNt) must not exceed 512 readings.
532 Cannot achieve requested resolution
  The multimeter cannot achieve the requested measurement resolution. You may have specified an invalid resolution in the CONFigure or MEASure command.
540 Cannot use overload as math reference
  The multimeter cannot store an overload reading (9.90000000E+37) as the math reference for null or dB measurements. The math state is turned off as a result of this condition.
550 Command not allowed in local
  The multimeter received a READ? command while in the local mode. For RS-232 operation, you should always execute the SYSTem:REMote command before sending other commands over the interface.
  Self-Test Errors
601 Front panel does not respond
602 RAM read/write failed
603 A/D sync stuck
604 A/D slope convergence failed
605 Cannot calibrate rundown gain
606 Rundown gain out of range
607 Rundown too noisy
608 Serial configuration readback failed
609 DC gain x1 failed
610 DC gain x10 failed
611 DC gain x100 failed
612 Ohms 500 nA source failed
613 Ohms 5 uA source failed
614 DC 1000V zero failed
615 Ohms 10 uA source failed
616 DC current sense failed
617 Ohms 100 uA source failed
618 DC high voltage attenuator failed
619 Ohms 1 mA source failed
620 AC rms zero failed
621 AC rms full scale failed
622 Frequency counter failed
623 Cannot calibrate precharge
624 Unable to sense line frequency
625 I/O processor does not respond
626 I/O processor failed self-test
  Calibration Errors
701 Cal security disabled by jumper
  The calibration security feature has been disabled with a jumper inside the multimeter. When applicable, this error will occur at power-on to warn you that the multimeter is unsecured.
702 Cal secured
  The multimeter is secured against calibration.
703 Invalid secure code
  An invalid calibration security code was received when attempting to unsecure or secure the multimeter. You must use the same security code to unsecure the multimeter as was used to secure it, and vice versa. The security code may contain up to 12 alphanumeric characters. The first character must be a letter.
704 Secure code too long
  A security code was received which contained more than 12 characters.
705 Cal aborted
  A calibration in progress is aborted when you press any front-panel key, send a device clear, or change the local/remote state of the multimeter.
706 Cal value out of range
  The specified calibration value (CALibration:VALue) is invalid for the present function and range.
707 Cal signal measurement out of range
  The specified calibration value (CALibration:VALue) does not match the signal applied to the multimeter.
708 Cal signal frequency out of range
  The input signal frequency for an ac calibration does not match the required input frequency for calibration.
709 No cal for this function or range
  You cannot perform calibrations for ac current, period, continuity, diode, ratio, or on the 100 MW range.
710 Full scale correction out of range
720 Cal DCV offset out of range
721 Cal DCI offset out of range
722 Cal RES offset out of range
723 Cal FRES offset out of range
724 Extended resistance self cal failed
725 500V DC correction out of range
730 Precharge DAC convergence failed
731 A/D turnover correction out of range
732 AC flatness DAC convergence failed
733 AC low frequency convergence failed
734 AC low frequency correction out of range
735 AC rms converter noise correction out of range
736 AC rms 100th scale linearity correction out of range
740 Cal checksum failed, secure state
741 Cal checksum failed, string data
742 Cal checksum failed, DCV corrections
743 Cal checksum failed, DCI corrections
744 Cal checksum failed, RES corrections
745 Cal checksum failed, FRES corrections
746 Cal checksum failed, AC corrections
747 Cal checksum failed, HP-IB address
748 Cal checksum failed, internal data

34132A Deluxe test lead kit with straight fixed sheath banana plugs
34132B Deluxe Test Lead Kit with straight retractable sheath banana plugs
  Includes 1.4 m flexible cable and a soft Sanoprene over mold for a comfortable grip. They are rated at 1000V CAT III. Contains red and black test leads, needle point and alligator test lead tips, and red and black retractable hook test leads.
11059A Kelvin Probe Set
  Use for making 4-wire Ohm measurements. The 4 color coded banana jacks and Kelvin clips are both gold plated for maximum conductivity and resistance to corrosion. The probe assembly also includes a ground to guard connector to help remove any ground related errors for the ultimate in high accuracy measurement. The wires are encased in a woven shroud for ease of use and to protect the cables.
11062A Kelvin Clip Set
  Silver plated Kelvin clips are ideal for constructing your own Kelvin Probe set for 4-wire Ohm measurements. Each set contains 2 clips.
34133A Precision Electronic Probe
  Designed specifically for working with small components and in dense circuit boards Length 1.2 m.
11060A Surface-Mount Device Probe
  The gold plated beryllium copper tweezer design provides an easy method to access and accurately measure SMD resistive networks. Length 1.2 m.
34171A DMM Terminal Connector
34172A DMM Calibration Short
11174A Low Thermal Lug to Banana Cable, length 1.2 m
11058A Low Thermal Banana to Banana Cable, length 1.2 m
E2301A Surface Type-K Thermocouple Probe
  Suitable for measuring surface temperature on PC boards. Accuracy ±2.2° C or ±.75%, whichever is greater. Tip is 0.25-in. diameter. Temperature range: –130° C (–200° F) to 260° C (500° F). Less than 2 second response time. Thermocouple: Chromel-Alumel. Must use with E2303A thermocouple probe adapter, uncompensated.
E2303A SMP-Dual Banana Adapter
E2307A Type-K Thermocouple Bead Temperature Probe
  General purpose temperature probe. Accuracy: –260°C to 110°C, ±2% of reading. Length: 0.9m. Terminated in dual banana plug.
E2308A Thermistor Temp Probe
  General purpose temperature probe. 5 KOhm @ 25° C, encapsulated in a stainless steel case. Temperature range: –80° C to 150° C. Accuracy: 0° C to 70° C, ±2%. Time constant: 3 seconds typical.
40653B Thermistor Surface Sensor Assembly
  10,000 Ohm thermistor with fast response gives real time measurements. Temperature range: –10° C to 100° C. Accuracy: ±1°C. termination: bare wire.
34302A Clamp-on ac/dc Current Probe
34134A AC/DC Current Probe
  Clamp on probe, Output signals: 1 V/A (1 mV/mA) and 10 mV/A. Frequency range: DC to 2 kHz.
34135A AC/DC Current Probe
  Clamp on probe, Measurement range 1 to 600A (Peak) AC and 1 to 600A DC. Output signal: 1mV/A, Frequency range: DC to 10 KHz.
34330A 30 A Current Shunt
  This current shunt can be used to extend the current measurement range. Precision 0.001 Ohm resistor. Output is 1 mV per amp of current passing through the shunt. 15 A continuous; 30A for 15 min continuous.
34397A 12 Vdc to 115V ac inverter
  Power instruments from a cigarette lighter with this dc-to-ac inverter.Accepts inputs from 10.5 to 15 V and provides 100 W max. power at 115 Vac.
Description of Model 34401A 
6 1⁄2 Digit Multimeter Performance Features
DC Volts
• 5 ranges: 0.1 V to 1000 V
• Basic 1 yr. accuracy: 35 ppm
• Maximum sensitivity: 100 nV
• Maximum reading rate: 1,000 rdg/s
• 7 ranges: 100 Ω to 100 M Ω
• Basic 1 yr. accuracy: 0.01%
• Maximum sensitivity: 10 μ Ω
• 2-wire and 4-wire Ω
AC Volts
• 5 ranges: 100 mV to 750 V
• Basic 1 yr. accuracy: 0.06%
• Bandwidth: 3 Hz to 300 kHz
• Maximum Reading Rate: 10 readings/s (50 readings/s with default delays defeated)
• Maximum Volt–Hz Product: 8 x 10 ^7
DC Current
• 4 ranges: 10 mA to 3 A
AC Current
• 2 ranges: 1 A to 3 A
• 3 Hz to 5 kHz bandwidth
Frequency and Period
• Range: 3 Hz to 300 kHz (333 ms to 3.33 μs)
• 1-Year Accuracy: 0.01% (40 Hz to 300 kHz); 0.05% (3 to 40 Hz)
• Resolution: 10 μHz to 1 Hz

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