Fluke 355 True RMS Clamp-Meter User Manual

Introduction

The Fluke 355 digital clamp-meter is a true RMS sensing, auto-ranging multimeter designed for precise measurement of current, voltage, frequency, and resistance in various electrical testing applications. It features a robust clamp mechanism for non-contact current measurement and a comprehensive set of functions for professional use, ensuring accurate readings for both linear and non-linear loads.

Safety Information

Always adhere to safety precautions when working with electrical equipment. This device is designed to meet IEC safety standard 61010-2-032.

• CAT IV, 600V: Suitable for measurements at the source of the low-voltage installation, such as electricity meters and primary over-current protection equipment.
• CAT III, 1,000V: Suitable for measurements within fixed installations, including switches and industrial equipment permanently connected to the fixed installation.

Ensure proper personal protective equipment (PPE) is used, and always follow local safety regulations when operating this device.

What's in the Box

Your Fluke 355 Clamp-Meter package includes the following components:

• Fluke 355 digital clamp-meter
• Test lead set
• Test probe set
• Alligator clip set
• (6) AA batteries
• Soft carrying case
• User manual

Image: All components included with the Fluke 355 Clamp-Meter, neatly arranged.

Product Features

• True RMS Sensing: Provides accurate readings for both linear and non-linear loads, regardless of waveform.
• High Current Measurement: Measures AC and DC current up to 2,000A (1,400A AC RMS).
• Large Jaw Opening: 58mm (2.3 inches) jaw opening accommodates large or multiple conductors for non-contact current measurement.
• Voltage Measurement: Measures AC voltage up to 600V and DC voltage up to 1,000V.
• Frequency and Resistance: Measures frequency up to 1kHz and resistance up to 400kΩ.
• Inrush Current Function: Analyzes surge current during motor startup and other inductive loads for stable measurements.
• Low-Pass Filter: Reduces high-frequency interference for accurate measurements of complex waveforms.
• Min/Max Function: Toggles to display lowest, highest, and average readings.
• Data Hold: Freezes the reading on the display for easy documentation in tight spaces.
• Continuity Buzzer: Confirms electrical continuity.
• Backlit LCD: Improves visibility in low-light conditions, with automatic backlight shut-off.
• Auto Power Off: Conserves battery life by automatically turning off after 20 minutes of non-use.
• Low-Battery Indicator: Signals when batteries need replacement.

Setup

Battery Installation

The Fluke 355 requires six 1.5V AA batteries for operation. These are typically included with your purchase.

1. Locate the battery compartment cover on the back of the device.
2. Use a screwdriver to open the cover.
3. Insert the six AA batteries, ensuring correct polarity (+/-).
4. Replace the battery compartment cover and secure it.

Initial Inspection

Before first use, inspect the clamp-meter, test leads, and accessories for any signs of damage. Do not use the device if any damage is observed.

Operating Instructions

Powering On/Off

Turn the rotary switch to any measurement function to power on the device. Turn the rotary switch to "OFF" to power off. The device will automatically power off after 20 minutes of inactivity to conserve battery life.

Measuring AC/DC Current (Clamp Function)

1. Turn the rotary switch to the "A AC+DC" position.
2. Press the jaw release lever to open the clamp jaws.
3. Position the clamp jaws around a single conductor. Ensure the jaws are fully closed.
4. Read the current value on the LCD.

Image: The clamp jaws of the Fluke 355 securely closed around an electrical conductor for current measurement.

Measuring Voltage (AC/DC)

1. Connect the test leads to the appropriate input jacks (COM and V).
2. Turn the rotary switch to the "V AC+DC" position.
3. Connect the test probes across the circuit or component to be measured.
4. Read the voltage value on the LCD.

Measuring Resistance (Ω)

1. Connect the test leads to the appropriate input jacks (COM and Ω).
2. Turn the rotary switch to the "Ω" position.
3. Ensure the circuit is de-energized before measuring resistance.
4. Connect the test probes across the component to be measured.
5. Read the resistance value on the LCD.

Other Functions

• RANGE: Manually select the measurement range if auto-ranging is not desired.
• HOLD: Press to freeze the current reading on the display. Press again to release.
• ZERO: Used to zero out DC current readings or resistance readings for lead compensation.
• Hz: Measures frequency.
• INRUSH: Measures the peak current during motor startup.
• MIN MAX: Toggles through minimum, maximum, and average readings captured during a measurement session.
• FILTER: Activates a low-pass filter to reduce electrical noise for stable readings.

Image: Detailed view of the Fluke 355 Clamp-Meter's display and control panel.

Maintenance

Cleaning

Clean the meter casing with a damp cloth and mild detergent. Do not use abrasives or solvents. Keep the display clean and dry.

Battery Replacement

When the low-battery indicator appears on the display, replace all six AA batteries promptly to ensure accurate measurements. Follow the battery installation steps outlined in the Setup section.

Storage

Store the clamp-meter in its soft carrying case in a dry, dust-free environment when not in use. Remove batteries if storing for extended periods to prevent leakage.

Troubleshooting

If the Fluke 355 Clamp-Meter is not functioning as expected, consider the following:

• No Display/Power: Check if the batteries are correctly installed and have sufficient charge. Replace batteries if necessary. Ensure the rotary switch is not in the "OFF" position.
• Inaccurate Readings: Verify that the correct measurement function is selected. Ensure test leads are properly connected and not damaged. For current measurements, ensure the clamp jaws are fully closed around a single conductor.
• Continuity Buzzer Not Working: Ensure the device is in the continuity measurement mode and the circuit is de-energized.

For persistent issues, refer to the official Fluke support resources or contact customer service.

Specifications

Warranty and Support

Fluke Corporation provides high-quality testing tools. For warranty information, technical support, or service, please visit the official Fluke website or contact their customer service department.

You can find more information and support resources at the Fluke Store on Amazon.