Fieldpiece Essential Clamp Meters

Quick Start

1. For electrical testing, connect test leads to "COM" and "+" jacks.
2. Rotate the dial to your desired measurement.
3. Connect to test points and read measurement.
4. For temperature testing, remove test leads, slide TEMP switch to the right and connect Type K thermocouple.

Certifications

UL 61010-1, Third Edition

EN61010-1, EN61010-2-032, EN61010-2-033

EMC EN61326-1

C-Tick (N22675)

WEEE

CATIII 600V, class II and pollution degree 2 indoor use comply with CE, RoHS compliant. CATIII is for measurements performed in the building installation.

Description

The SC400 series clamp meters are designed for HVACR service. They feature a redesigned heavy-duty magnet for hanging on metallic surfaces (SC440 only). The dual LCD display shows both voltage and amperage readings simultaneously, with a bright blue backlight for low-light conditions (SC440 only). A single test lead holder allows for one-handed operation and added safety. Test leads have removable gold-plated tips compatible with Fieldpiece accessory heads.

The SC440 model offers True RMS sensing for more accurate VAC and AAC readings on VFDs, and an Inrush current feature to measure the starting amp draw of a compressor. An automatic clamp jaw light (SC440 only) helps identify the wire being tested. These meters are built with high-impact plastic to withstand HVACR rigors and provide accurate temperature measurements in varying environments.

Controls

Rotate the dial to select the desired function:

• OFF
• VAC (Voltage AC)
• VDC (Voltage DC)
• AAC 50A / 400A (Amps AC)
• Hz (Frequency)
• °F / °C (Temperature)
• % (Duty Cycle)
• µADC (MicroAmps DC)
• MFD (Capacitance)
• NCV (Non Contact Voltage)
• Ω (Resistance)

Buttons:

• SELECT: Cycles through parameters within VAC/AAC/Hz and Ω/°F/MFD/NCV functions.
• RANGE HOLD: Manually select a range or freeze the display.
• INRUSH (SC440 only): Activates inrush current measurement and scrolls through inrush ranges.
• TEMP K-TYPE 30V MAX: Used for Type K thermocouple connection.
• AUTO OFF: Auto Power Off feature.
• TRUE RMS (SC440 only): Indicates True RMS measurement capability.
• COM: Common test lead jack.
• Backlight (SC440 only): Illuminates the display.

Display Indicators

• Battery Life: Battery icon blinks when replacement is needed.
• Auto Power Off Enabled: Indicates APO is active.
• High Voltage Warning (>30VAC/VDC): Indicates voltage above 30V.
• Manual Range (RNG) Mode: Indicates manual range selection.
• Data Hold Mode: Indicates the display is frozen.
• Inrush Amps Mode (SC440 only): Indicates Inrush current measurement is active.
• Continuity Test: Indicates continuity is detected (audible beep and green LED).
• Diode Test: Indicates diode test status.
• Frequency Test (hertz): Displays frequency measurement.
• Resistance Test (ohms): Displays resistance measurement.
• Capacitance Test (farads): Displays capacitance measurement.
• Duty Cycle Test (percentage): Displays duty cycle measurement.
• Micro Unit (µ): Indicates 10⁻⁶ multiplier.
• Milli Unit (m): Indicates 10⁻³ multiplier.
• Kilo Unit (k): Indicates 10³ multiplier.
• Mega Unit (M): Indicates 10⁶ multiplier.

Safety Information

• Never ground yourself when taking electrical measurements.
• Do not touch exposed metal pipes, outlets, or fixtures while taking measurements. Isolate yourself from ground using dry clothing, rubber shoes, or rubber mats.
• Disconnect test leads before opening the case. Inspect leads for damage and replace if suspect.
• Keep fingers behind finger guards on probes.
• When disconnecting from a circuit, disconnect the "RED" lead first, then the common "BLACK" lead. Use one-handed testing when possible. Work with others.
• Turn off power before cutting, unsoldering, or breaking a circuit.
• Do not measure resistance (ohms) on a powered circuit. Isolate loads by disconnecting them.
• Disconnect the meter from the circuit before turning off any inductor, including motors, transformers, and solenoids, to prevent damage from high voltage transients.
• Do not use during electrical storms.
• Do not apply more than rated voltages between input and ground.
• Isolate capacitors from the system and discharge them safely before testing.
• The temperature switch prevents measuring voltage with the thermocouple plugged in.
• When measuring high frequency AC current, do not exceed the rated 400AAC. Failure to do so may cause the clamp to heat up dangerously.
• All voltage tests: All voltage ranges will withstand up to 600V. Do not apply more than 600VDC or AC rms.

Symbols:

• ⚠️ Caution, risk of electric shock
• ⓘ Caution, refer to manual.
• ⏚ Ground
• ⛶ Double insulation

WARNINGS:

• DISCONNECT AND UNPLUG TEST LEADS before opening case.
• TEST NCV FUNCTION ON KNOWN LIVE WIRE before using.
• DO NOT APPLY VOLTAGE greater than 30VAC or 60VDC to the thermocouple or the jacks when the rotary dial is on °F/°C. (Use only Type K thermocouples)
• DO NOT APPLY VOLTAGE TO THE JACKS when the rotary dial is on microamps. Even low voltages can cause a current overload and potentially harm the meter.

Specifications

• Display: 5000 count dual display
• Backlight: 60-second duration with auto-off. Blue color (SC440 only).
• Overrange: "OL" or "-OL" is displayed.
• Measurement rate: 3.3 times per second, nominal.
• Zero: Automatic.
• Operating environment: 32°F to 122°F (0°C to 50°C) at <70% relative humidity.
• Storage temperature: -4°F to 140°F (-20°C to 60°C), 0 to 80% RH (with battery removed).
• Accuracy: Stated accuracy @ 73°F±9°F (23°C±5°C), <75%RH.
• Temperature coefficient: 0.1 x (specified accuracy) per °C [0°C to 19°C (32°F to 66°F), 28°C to 50°C (82°F to 122°F)].
• APO (Auto Power Off): Approx. 30 minutes.
• Power: Single standard 9-volt battery (NEDA 1604, JIS 006P, IEC 6F22).
• Battery life: 200 hours typical alkaline (SC420); 100 hours typical alkaline (SC440).
• Low battery indication: Battery icon blinks and "LO.bt" is displayed when battery voltage drops below operating level.
• Dimensions: 233mm(H) x 79mm(W) x 45mm(D).
• Weight: Approx. 315g including battery.
• Altitude: Up to 6562 ft (2000m).
• Overload protection: 600 VDC or 600VAC rms unless otherwise stated.
• Test leads: Use UL listed test leads complying to UL61010-031 rated CATIII 600V or above. Included leads are gold-plated with removable safety caps.

Please operate the instrument following all instructions of the operator's manual to avoid impairing the safety of the product.

Functions

Temperature (°F/°C)

Connect a Type K thermocouple directly to the meter to measure temperature. The meter has internal cold junction compensation for accurate measurements in changing ambient temperatures. No adapter is required.

• Range: -30°F to 932°F, (-35°C to 500°C)
• Resolution: 0.1°
• Accuracy: ±(1°F)* for 32°F to 120°F, ±(1°C) for 0°C to 49°C; ±(1%+2°F) for 32°F to 572°F, ±(1%+1°C) for 0°C to 300°C; ±(2%+6°F) for -30°F to 32°F, ±(2%+3°C) for -35°C to 0°C; ±(2%+6°F) for 572°F to 932°F, ±(2%+3°C) for 300°C to 500°C. (*After field calibration)
• Sensor type: Type K thermocouple
• Overload protection: 30 VDC or 30VAC rms

Non Contact Voltage (NCV)

Use NCV to check for 24VAC from a thermostat or live voltage up to 600VAC. Always test a known live source before using. A segment graph and RED LED indicate the presence of voltage. An audible beep increases in frequency as the field intensity increases.

• AC Voltage Detection Range: 24VAC to 600VAC (50-60Hz)

Voltage AC (VAC) (50Hz-500Hz)

Test power lines (120V, 220V, 480V), 24V controls, and transformer failures.

• Ranges: 500mV, 5V, 50V, 500V, 600V
• Resolution: 0.1mV
• Accuracy: ±(1.2% + 8) for 500mV range (50-60Hz); ±(1.2%+8) for 5V, 50V, 500V; ±(1.5% + 8) for 600V range.
• True RMS: SC440 model only.
• Crest factor: ≤ 3
• Audio/Visual Hi-V indicator: >30VAC/VDC
• Input impedance: >100MΩ (500mV), 10MΩ (5V), 9.1MΩ (50V-600V)

MicroAmps DC (µADC)

Used for flame rectifier diode tests on heater controls. Connect leads between the flame sensor probe and control module. When the flame is on, a measurable µADC signal (typically under 10µADC) should be present. Compare to manufacturer specifications.

• Ranges: 500µA
• Resolution: 0.1µA
• Accuracy: ±(1.0% + 2)
• Voltage burden: 1V
• Overload Protection: 600VDC or 600VAC rms

Frequency (Hz) Through Leads

Check incoming voltages for 60Hz cycling. Use the amp clamp for frequency measurements on VFD equipment.

• Ranges: 500Hz, 5kHz, 50kHz, 500kHz, 1MHz
• Resolution: 0.1Hz
• Accuracy: ±(0.1% + 5)
• Sensitivity: 10Hz to 1MHz: >3.5Vrms
• PW: >1µs
• Duty Cycle Limits: >30% and <70%

Duty Cycle (%)

Shows the % On Time of a 5V logic signal square wave.

• Ranges: 5%-95% (40Hz to 10kHz), 10%-90% (10kHz to 20kHz)
• Accuracy (5V logic): ±(2% + 10)
• Resolution: 0.1%
• PW: >10µs
• Overload Protection: 600VDC or 600VAC rms

Capacitance (MFD)

Test motor start and run capacitors. Capacitors are common failure points in HVACR systems. Discharge capacitors before testing. "dIS.C" is displayed if not fully discharged.

• Ranges: 5µF, 50µF, 500µF, 5mF
• Resolution: 1nF
• Accuracy: ±(3% + 15) for 5µF, ±(3% + 5) for 50µF to 500µF, ±(5% + 20) for 5mF.
• Overload Protection: 600VDC or 600VAC rms

Voltage DC (VDC)

Measure DC voltages on circuit boards in advanced HVACR systems.

• Ranges: 500mV, 5V, 50V, 500V, 600V
• Resolution: 0.1mV
• Accuracy: ±(0.5% + 2)
• Input impedance: >100MΩ (500mV), 10MΩ (5V), 9.1MΩ (50V-600V)

Resistance (Ω)

Used for testing compressor windings. 0.1Ω resolution is necessary for testing resistance between motor poles due to typically low values.

• Ranges: 500Ω, 5kΩ, 50kΩ, 500kΩ, 5MΩ, 50MΩ
• Resolution: 0.1Ω
• Overload Protection: 600VDC or 600VAC rms
• Accuracy: ±(1.0% + 5) for 500Ω to 500kΩ, ±(1.5% + 5) for 5MΩ, ±(3.0% + 5) for 50MΩ

Continuity (Beep)

Tests if a circuit is open or closed, useful for checking fuses. A steady "beep" and green LED indicate continuity.

• Range: 500Ω
• Resolution: 0.1Ω
• Response time: 100ms
• Audible beep: <30Ω
• Overload Protection: 600VDC or 600VAC rms

Diode Test (LED)

Tests diodes for proper forward and reverse-biased functions.

• Test current: 0.8mA (Approx.)
• Accuracy: ±(1.5% + 5)
• Open circuit volts: 3.2VDC typical
• Audible beep: <0.03V
• Visual Indicator: Green LED
• Overload Protection: 600VDC or 600VAC rms

Amps AC (AAC) True RMS

Test any isolated power line. Press SELECT on VAC/AAC/Hz position. Read AAC in the upper display. True RMS is available on the SC440 model only.

• Ranges: 50A, 400A
• Resolution: 0.01A
• Crest factor: ≤ 3
• Accuracy: ±(2.0% + 10) for 50-60Hz
• Jaw Opening: 1.2in (30 mm)

Frequency (Hz) Through Clamp

Measure Hz on variable frequency drive motors. Turn dial to VAC/AAC/Hz and press SELECT twice. Hz will show in the upper display.

• Range: 10Hz to 400Hz
• Accuracy: ±(0.1% + 5)
• Minimum current range: > 5AAC
• Overload Protection: 400AAC
• Resolution: 0.1Hz

Inrush Current (SC440 only)

Captures the starting current of a compressor motor, which can help diagnose motor issues before failure.

1. Turn selector switch to VAC/AAC/Hz.
2. Press SELECT once to show AAC on the upper display.
3. Press INRUSH once for the 50AAC range, or twice for the 400AAC range.
4. Clamp the meter around the compressor start wire and turn the motor on. The starting current will hold on the upper display.
5. Hold INRUSH for 2 seconds to exit, or press and release INRUSH to measure starting current again.

• Inrush measurement period: 100 milliseconds
• Minimum input: >2A on 50A range; >20A on 400A range

Note: AAC through the clamp and voltage through the test leads can be measured simultaneously. However, if only AAC, Frequency (Hz), or Inrush is measured through the clamp, test leads and thermocouple must be unplugged from the meter.

Modular Expandability

The Swivel Clamp Meter is compatible with all Fieldpiece Accessory Heads, allowing measurement of various parameters displayed in real-time. To use an accessory head, set the range to VDC and press RANGE until mV is displayed. Remove probe tips and connect the accessory head (e.g., AAV3 shown). Visit www.fieldpiece.com for a full list of accessory heads.

Temp. Calibration

For ±1°F accuracy, calibrate to a known temperature. A stabilized ice water mixture (approx. 32°F/0°C) is recommended.

1. Select the °F/°C range.
2. Plug the thermocouple into the Type K jack.
3. Remove the battery cover (use magnet strap on SC440).
4. Prepare a large cup of ice water and stir until the temperature stabilizes.
5. Immerse the thermocouple probe, ensuring it does not contact ice directly. Stir water to prevent micro-environments.
6. Adjust calibration pot C (located below the battery) with a small screwdriver to match the stable ice water temperature (e.g., 32°F/0°C).

Note: J1-J2 switch is for auto calibration purposes only; do not switch from J2.

Auto Power Off

The Auto Power Off (APO) feature automatically turns off the meter after 30 minutes of inactivity. APO is active by default and indicated on the display. To disable APO:

1. Turn the meter to OFF.
2. Hold the HOLD button and turn the selector dial to any range.
3. Release HOLD after the beep. APO will no longer display.

Auto Hold

Press and hold the HOLD button for two seconds. The meter will beep, and "HOLD" will blink on the LCD. After 6 seconds, the measurement will freeze automatically. Press HOLD again to exit this mode.

Battery Replacement

When the battery is low, the battery icon will blink for 30 seconds, "LO.bt" will display, and the meter will power off. Turn the dial to OFF, disconnect test leads, and remove the battery cover (use magnet strap on SC440). Replace with a standard 9V battery. Re-insert the magnet strip before replacing the cover.

Maintenance

Clean the exterior with a dry cloth. Do not use liquid cleaners.

Limited Warranty

This meter is warranted against defects in material or workmanship for one year from the date of purchase. Fieldpiece will replace or repair defective units at its option, subject to verification of the defect. This warranty does not cover defects resulting from abuse, neglect, accident, unauthorized repair, alteration, or unreasonable use. Implied warranties of merchantability and fitness for a particular purpose are limited to one year. Fieldpiece is not liable for loss of use or consequential damages.

Obtaining Service

For out-of-warranty service pricing, contact Fieldpiece Instruments. For in-warranty service, send proof of purchase date and location. Ship the meter freight prepaid to Fieldpiece Instruments. International customers should contact local distributors for warranty service.

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© Fieldpiece Instruments, Inc 2014; v21