Tektronix DMM4050 6 half bit high-precision digital multimeter



Tektronix DMM4050 6 half bit high-precision digital multimeter

Basic Information and Core Positioning

Product positioning: 6 1/2 high-precision digital multimeter, specializing in laboratory precision measurement (such as reference voltage source calibration) and industrial production line testing (such as component parameter screening), balancing high resolution and wide measurement range.

Summary of Core Specifications

Measurement Function Range Accuracy (Typical Value) Resolution (Highest)

DC voltage (V DC) 10 μ V -1000V ± (0.0025% reading+0.0005% range) 1 μ V (2V range)

AC voltage (V AC) 100 μ V -1000V ± (0.02% reading+0.005% range) (50Hz/60Hz) 10 μ V (20V range)

DC current (I DC) 100nA-10A ± (0.01% reading+0.002% range) 10nA (200 μ A range)

AC current (I AC) 100nA-10A ± (0.05% reading+0.01% range) (50Hz/60Hz) 10nA (200 μ A range)

Resistance (Ω) 10m Ω -100M Ω± (0.005% reading+0.0005% range) 1m Ω (200 Ω range)

Capacitor (F) 100pF -100 μ F ± (0.5% reading+0.1% range) 1pF (2nF range)

Operation Guide: Panel Control and Basic Measurement

1. Key components of the front-end panel

Specific functional operation examples for component categories

Function selection area MEAS key: Switch measurement functions (V DC/V AC/I DC, etc.) Press MEAS → Rotate knob to select "V DC"

Range control area RANGE key: manually switch range; AUTO button: Press AUTO for automatic range, and the instrument will automatically match the 10V range (measure 5V signal)

HOLD in the data operation area: Freeze the current reading; STORE: Store data by pressing STORE → select "INT" (internal storage)

Menu control area CONFIG: Enter system configuration; MATH: For mathematical operations, press CONFIG → select "PLAY" to adjust the backlight

Display area 7-segment LCD: displays reading, unit, and status (such as "OVER" exceeding limit). When measuring 10V DC, it displays "10.00000 V DC"

2. Basic measurement process (taking DC voltage as an example)

Power on and self-test:

Press the POWER button, the instrument performs a 3-second self-test (ROM/RAM/ADC), displays "DMM4050", and then enters standby mode;

If the self-test fails (such as displaying "ERROR -121"), refer to the "Troubleshooting" section for repair.

Function and range settings:

Press MEAS → Rotate knob to select "V DC";

Press AUTO to enable automatic range (or press RANGE to manually select "10V" range).

Connection and measurement:

Connect the red probe to the "V Ω" terminal and the black probe to the "COM" terminal;

Connect the tested signal (such as a 5V reference source) and display the reading on the LCD (such as "5.00000 V DC").

Data processing:

Freeze the reading according to HOLD; Store internally according to STORE (up to 2000 sets);

Press VIEW to view stored data (knob to switch to previous/next).

Advanced features: Mathematical operations and limit testing

1. Mathematical operation function

Basic operations: Supports "+/-/×/÷" and "√", requires storing 2 data (STORE → 1/2) first, and then press MATH → select the operation type;

Example: Measure two resistors R1=100 Ω and R2=200 Ω, select the "+" operation, and the result shows "300000 Ω".

Special operations:

DB/dBm calculation: used for audio/RF signals, follow MATH → dB → select reference value (e.g. 0dBm=1mW);

Relative measurement (Δ): Press MATH → Δ → to store the reference value, and subsequent readings will display the difference from the reference (e.g. reference 5V, measuring 5.0001V will display "+0.0001V").

2. Extreme testing function

Function purpose: Set upper and lower limits, trigger alarms when exceeding limits (LED red light+beep), suitable for batch screening on production lines;

Operation steps:

Press Limit → select "HI/LO" (upper/lower limit);

Set the limit value for rotating knob (such as HI=110 Ω and LO=90 Ω when measuring resistance);

Press START to start the test, the reading will display "IN" (green light) within 90 Ω -110 Ω, and "OUT" (red light+beep) when exceeding the limit.

3. Remote control (GPIB/USB)

Interface specifications:

GPIB: Supports IEEE 488.2 protocol, Talker T6/Listener L4， Address 0-31 can be set;

USB: Compatible with USBTMC protocol, supports plug and play (no driver required).

SCPI command example:

Measure DC voltage (10V range, 0.001 resolution): MEASure: VOLTage: DC?  10,0.001；

Read stored data (Group 10):: DATA: READ?  10；

Set GPIB address: SYSTem: GPIB: DDRess 22.

Calibration and maintenance

1. Self calibration process

Trigger condition:

Regular triggering: recommended for 90 days (stable environment temperature ± 2 ℃) and 30 days (environment fluctuation>5 ℃);

Manual trigger: Press and hold the CAL key when turning on, or press CONFIG → CAL → START.

Calibration steps:

Disconnect all probes, the instrument displays "CALIBRATION...";

Internal calibration of ADC and reference source (approximately 2 minutes), displaying "CAL PASS" upon completion;

If 'CAL FAIL' is displayed, check the ambient temperature (+18 ℃ -+28 ℃) and recalibrate.

2. Error correction

External correction: When the measurement accuracy exceeds the limit, the correction value can be entered (CONFIG → CAL → CORECT);

Example: Measure a 10V reference source, read 10.0001V, enter the correction value "-0.0001V", and the subsequent readings will be automatically compensated.

Temperature compensation: The instrument has a built-in temperature sensor that automatically compensates for resistance/capacitance measurements (± 0.001%/℃).

3. Troubleshooting

Possible causes and solutions for the fault phenomenon

No display/power adapter failure, fuse blown, replace with 12V/3A adapter; Check the "FUSE" terminal (2A/250V fuse)

The reading drift is too large and self calibration is not performed due to environmental temperature fluctuations; Ensure stable ambient temperature (± 1 ℃/hour)

GPIB unresponsive address mismatch, cable loose confirmation GPIB address (: SYST: GPIB: ADRD?); Replace GPIB cable

Error Code -221 Parameter Out of Range Check Command Parameters (e.g. MEAS: VOLT: DC?)? 2000 over 1000V range)

Safety and Environmental Compliance

1. Safety level and operating standards

Overvoltage category: CAT III 1000V (distribution system), CAT IV 600V (low-voltage power grid);

Terminal rating:

V Ω terminal: maximum 1000V DC/AC;

Terminal A: Maximum 10A DC/AC (continuous), 20A (30 second pulse);

Safe operation: It is prohibited to plug or unplug probes with power on; Wear insulated gloves when measuring>600V; Stop using when the terminal is damaged.

2. Environmental parameters

Explanation of Environmental Category Specification Requirements

If the working temperature exceeds the range of+18 ℃ -+28 ℃, the self calibration cycle needs to be extended (e.g. once every 30 days for+10 ℃ -+18 ℃)

Storage temperature -40 ℃ -+70 ℃. Storage in humid/corrosive environments is prohibited

When the humidity is between 20% and 80% (without condensation), dehumidification is required before use when the humidity is above 80%

Altitude ≤ 2000m, high altitude (>2000m) requires derating for use (e.g. voltage range x 0.8)