1. Introduction and Overview
The Keysight U1253B is a 4.5-digit handheld digital multimeter (DMM) designed for troubleshooting electronics and electrical circuits. It features an Organic LED (OLED) display for clear readings in various lighting conditions, including dark or off-angle situations. This DMM includes an integrated 20 MHz frequency counter, a built-in programmable square-wave generator, and data-logging capabilities for PC integration.
Figure 1: Front view of the KEYSIGHT U1253B Handheld Digital Multimeter, showing the OLED display, rotary dial, and function buttons.
2. Safety Information
This product is intended for professional use only.
Keysight Technologies products are classified as industrial monitoring and control equipment designed exclusively for professional or industrial use and related training programs. Keysight products are designed and certified to meet national industrial safety standards (such as Electrical Equipment for Measurement, Control and Laboratory Use) where products are sold solely for use by trained professionals. Keysight products are not intended for consumer use in a residential setting and may not meet consumer level standards for EMC and other regulated radiated emissions. Keysight products are intended for use in the country where the product was originally sold.
Always adhere to local and national safety regulations when operating the device. Ensure proper insulation and grounding practices are followed to prevent electrical shock or damage to the instrument.
3. Product Features
- 30,000 counts resolution for precise measurements.
- 0.7% accuracy for AC voltage measurements.
- Low Pass Filter (LPF) for accurate readings in noisy environments.
- Quick signal type identification (Qik-V).
- Internal memory capable of storing up to 200 data points for logging.
- Dust and water resistant casing (IP 54 compliant) for enhanced durability.
- Organic LED (OLED) display for superior visibility.
- Integrated 20 MHz frequency counter.
- Built-in programmable square-wave generator with selectable frequency and duty cycle.
4. Setup
4.1 Battery Installation and Charging
The U1253B uses a rechargeable 9-volt battery. To install or replace the battery, refer to the back panel of the device. Ensure the battery is correctly oriented according to the polarity markings. Use the provided charger to fully charge the battery before initial use. Regular charging is recommended due to the OLED display's power consumption.
Figure 2: Back view of the multimeter, indicating the battery compartment.
4.2 Connecting Test Leads
Insert the test leads into the appropriate input jacks on the front panel of the multimeter. For most measurements, the black lead connects to the 'COM' (common) jack, and the red lead connects to the 'V Ω Hz' or 'A' (current) jack depending on the measurement type. Always ensure secure connections.
5. Operating Instructions
5.1 Basic Operation
Turn the rotary dial to the desired measurement function. The OLED display will show the selected function and measurement range. Use the 'Range' button to manually select a range or allow the DMM to auto-range. The 'Hold' button can freeze the current reading on the display.
Figure 3: Angled view of the multimeter, showing the display and control layout.
5.2 Voltage Measurement (AC/DC)
Rotate the dial to the 'V∼' (AC Voltage) or 'V—' (DC Voltage) position. Connect the test leads in parallel to the circuit or component under test. The display will show the voltage reading. Use the 'Shift' button to toggle between AC and DC if the dial position covers both.
5.3 Current Measurement (AC/DC)
Rotate the dial to the 'A∼' (AC Current) or 'A—' (DC Current) position. Ensure the red test lead is connected to the appropriate current input jack (e.g., 'mA µA' or 'A'). Connect the DMM in series with the circuit. Exercise caution when measuring current, as incorrect connection can damage the meter or circuit.
5.4 Resistance Measurement
Turn the dial to the 'Ω' (Resistance) position. Connect the test leads across the component to measure its resistance. Ensure the circuit is de-energized before measuring resistance.
5.5 Frequency Counter
To use the integrated 20 MHz frequency counter, select the 'Hz' function. Connect the test leads to the signal source. The DMM will display the frequency of the input signal.
5.6 Square-Wave Generator
The U1253B includes a programmable square-wave generator. Refer to the detailed manual for specific instructions on setting frequency and duty cycle for output generation.
5.7 Data Logging
The DMM has internal memory for up to 200 data points. For extended data logging and analysis, utilize the easy-to-use GUI data-logging software provided by Keysight, which allows for automated and virtually unlimited data recordings to a PC.
6. Maintenance
6.1 Cleaning
Clean the exterior of the multimeter with a soft, damp cloth. Do not use abrasive cleaners or solvents. The device is dust and water resistant (IP 54 compliant), but avoid submerging it in liquids.
6.2 Battery Care
Regularly charge the 9-volt rechargeable battery. If the meter will not be used for an extended period, it is advisable to fully charge the battery and store the meter in a cool, dry place. Be aware that the OLED display can consume significant power, potentially leading to shorter battery life compared to meters without OLED displays. Monitor the battery indicator and charge as needed.
7. Troubleshooting
7.1 Display Not Working or Dim
If the OLED display is dim or not functioning, first check the battery charge level. A low battery can affect display performance. If the issue persists after charging, contact Keysight support. While OLED displays offer excellent clarity, some users have reported issues with display longevity over time.
7.2 Short Battery Life
The U1253B's OLED display and advanced features contribute to higher power consumption. If you experience unusually short battery life, ensure the battery is fully charged and consider carrying a spare or having charging facilities readily available. The 9-volt battery may not provide as long a runtime as other battery configurations found in simpler DMMs.
7.3 Inaccurate Readings
Verify that the test leads are correctly connected and not damaged. Ensure the rotary dial is set to the appropriate function and range for the measurement. If measuring in noisy electrical environments, ensure the Low Pass Filter (LPF) is engaged if applicable. If inaccuracies persist, the device may require calibration or service.
8. Specifications
- Model: U1253B
- Display: 4.5-Digit Organic LED (OLED)
- Resolution: 30,000 counts
- ACV Accuracy: 0.7%
- Frequency Counter: Integrated 20 MHz
- Signal Generator: Programmable Square-Wave (selectable frequency and duty cycle)
- Data Logging: Internal memory for up to 200 readings
- Environmental Protection: Dust and water resistant (IP 54 compliant)
- Power Source: Rechargeable 9V battery
9. Warranty and Support
For information regarding warranty coverage, technical support, or service, please refer to the official Keysight Technologies website or contact their customer service department directly. Ensure you have your product model number (U1253B) and purchase details available when seeking support.
