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Fieldpiece SC77
True RMS HVAC/R Clamp Meter
See: SC640

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Fieldpiece SC77 Shown
Product Information
Datasheet 929 KB PDF Datasheet
Manual 521 KB PDF Datasheet
PDF HelpPDF Help
  • Works with all Accessory Heads
  • True RMS Voltage Readings
  • MicroAmps DC for Flame Diodes
  • Non-Contact Voltage
  • High Voltage Alert
  • Temperature Ranges up to 1000°F
  • AC Volts
  • DC Volts
  • Resistance (Ohms)
  • Diode Test
  • Rugged ABS case
  • Lead Storage on Back
  • Ergonomic shape fits naturally in your hand
  • Auto power-off (APO) to conserve battery life

The Fieldpiece SC77 True RMS HVAC/R Clamp Meter is one of our most popular digital multimeters for a reason. The Fieldpiece SC77 has virtually every parameter for electrical and thermal HVAC/R testing in one meter. This auto ranger includes a host of safety features including a high-voltage LED and beeper, a continuity warning, push button non-contact voltage (NCV), a lead holder with detachable leads and alligator probe tips for easy one-handed testing. As far as ranges go, the Fieldpiece SC-77 Clamp Meter has temperature, capacitance, microamps DC for flame diode tests, and everyday electrical ranges for HVAC/R. Not to mention technicians tell us it one of the most durable meters in the industry. Rivaled only by our stick meters, the Fieldpiece SC 77 is also one of their top picks from Fieldpiece.

You can tell the difference simply by putting the Fieldpiece SC77 in your hand. It’s a natural fit; the Fieldpiece SC77 feels solid and has a bit of balanced weight to it. Add to that True RMS and virtually every electrical parameter the user is going to need for HVAC/R field service. Add to that temperature and the fact that it works with Fieldpiece accessory head instruments, and finally add to that built-in safety features, detachable leads, and warnings, and the Fieldpiece SC-77 is a powerful, affordable meter.


Designed specifically for HVAC/R field service, the Fieldpiece SC77 is a dedicated DMM and offers specific features and benefits to HVAC/R field service pros including:

Works with Fieldpiece Accessory Heads
There is a Fieldpiece accessory head available for just about any job. There are heads to measure temperature, superheat, subcooling, RH%, wet bulb, dew point, vacuum (microns of mercury), manometer (inches of water column), amps AC&DC, high voltage, CO, %CO2, air velocity, and many more.

Non-contact Voltage
With the NCV tab on the tip of the clamp close to an AC voltage, press and hold the NCV button. The NCV LED will light with an analog feel and the beeper will beep. The closer you get to AC voltage, the louder the beep. The NCV function is sensitive enough to detect 24VAC on thermostats (24V to 600V, 50Hz to 60Hz).

High Voltage and Continuity Indicators
If the user is using the High Voltage and Continuity Indicators while doing lab testing, these features would probably drive you crazy. Fieldpiece took input from more than one HVAC/R veteran in order to make sure that these features really remind the user of what they're doing and they’ve avoided potentially dangerous situations in the field. The Hi-V LED and beeper let you know when you’ve hooked up to a circuit over 30V. The continuity LED and beeper tells the user if a circuit is open or closed.

Using the built-in amp clamp, the user can use the Fieldpiece SC 77 to read 0-200 amps directly on your meter with 0.1 resolution.

Capacitance (MFD)
With the Fieldpiece SC76, users can measure microfarads on motor-run and motor-start capacitors using the Capacitance range. To use, first disconnect the capacitor from power first, then Short the terminals to discharge the capacitor. Disconnect any resistors that might be between the terminals of the capacitor and measure to check for degradation.


Take ambient air or refrigeration line temperatures and more with the built-in K-type port and the included the Fieldpiece ATB1 wrap tab thermocouple. Add a wet sock (saturated tissue or a shoelace to take wet bulb temperatures. The built-in temperature junction offers great temperature compensation for more accurate and faster measurements.

Microamps DC - Flame Rectification Tests
The most common "no heat" call has to do with a malfunctioning flame sensing diode. Simply turn the Fieldpiece SC76 Clamp Meter to microamps DC, hook up, and see if the flame sensing rod is functioning properly.

True RMS
Digital multimeters use two different types of AC sensing. The most common is average sensing, normalized to a true RMS value of a sine wave. The other is true RMS sensing. The actual true RMS value is sensed for a wave form within the limits of the crest factor. Either sensing method will give the same results on a clean sine wave but they may differ on a non-sinusoidal waveform.

Fieldpiece ADK7 attached lead clip on the to help you perform a one-hand test more easily than most meters

Silicone Leads with Detachable Probe Tips
Because the wire insulation is silicone, the leads stay flexible in cold weather and will not melt if bumped by a soldering iron. Use the attached lead clip on the to help the user perform a one-hand test more easily than most meters on the market. Built-in lead storage makes it easy to keep everything together from job to job. Fieldpiece's Deluxe Silicone Lead Kit, model ADK7, is an optional purchase from your favorite distributor and makes one-handed testing even easier.

Wire Grabbing Jaw
The Fieldpiece SC 76's fixed jaw is longer than the moveable jaw to make it easier to select just one wire from a bundle. With the jaws closed, separate one wire using the long fixed jaw then slide it to the corner where the two jaws meet; Finally, open the jaws to let it in. Now you can select the wire without holding the jaws open.

Bright Blue Backlight
Easily read the display in overcast conditions or in dimly lit areas.

The HOLD button is easily pressed while holding the mini clamp meter naturally in your hand. The Fieldpiece SC-76 holds any reading on your meter so you can concentrate on the test points and look at the LCD after the user has disconnected.

Fieldpiece SC77 Dial Settings/Ranges
Selecting Ranges
For DC voltage, set the meter to the VDC parameter instead of VAC as shown below. For all ranges and functions choose a range just above the value you expect. If display reads "OL" (overload), select a higher range. If display shows less than three numbers, select a lower range for better resolution.
Function Range Accuracy
Display Counts 2000 n/a
AC Volts (2,3) 200 1.2% + 3 / 0.1
600 2% + 5 / 1
AC Amps 200 3% + 5 / 0.1 (1)
DC Volts (2) 200 0.5% + 1 / 0.1
DC Amps (Series)(4) 200µ 1% + 1 / 0.1
Resistance (Ohms)(9) 200 1%+3 / 0.1
200K 1% + 3 / 0.1k
Microfarads (6) 200 3% + 5 / 0.1
Temperature (°F) (5) 200 1°F / 0.1
1000 1% + 1.5°F / 1
Continuity Check (10) Yes
Diode Test Yes
Diode Test (7) Yes
Probe Storage Yes
NCV (8) Yes
MAX Hold (11) Yes
Amp OL Protection PTC

(1) - 50-60Hz
(2) - Input impedance is 560Kohms on volts ranges, 10Mohm on millivolts ranges. All ranges will withstand 600VAC/600VDC
(3) - 50Hz-500Hz
(4) - Protected by PTC (positive temperature coefficient) resistor. If an overload occurs on microamps DC, disconnect from circuit for 30 seconds so the PTC can reset
(5) - Accuracy 1OF (32OF to 120OF); 1%+1.5OF (-4OF to 750OF); 2%+4OF (-30OF to -4OF, 750OF to 1000OF); all withstand 30V max
(6) - Test frequency 34Hz at >3.5V. Will withstand up to 500V
(7) - Turns on <30V
(8) - Senses 24VAC to 600VAC
(9) - 0.3VDC typical open circuit voltage.(3V on 200ohm range). Withstands up to 500V on any ohms range
(10) - Turns on >100 ohms within 100mS. Will withstand up to 500V
(11) - Holds highest reading
AC Volts (50Hz - 500Hz)
Ranges: 4V, 40V, 400V, 600V
Resolution: 1mV
Accuracy: ±(2.0% rdg + 8 dgts) 50 ~ 500Hz
Input impedance: 3MΩ
Overload protection: 600V DC or AC rms
Transient protection: 6kV for 10μ sec
AC Current (50Hz - 60Hz)
Ranges: 40A, 300A
Resolution: 0.01A
DC Accuracy: ±(3.0% rdg + 10 dgts) 0 ~ 300A / 50 ~ 60Hz
Overload protection: 300AAC
DC Volts
Ranges: 400mV, 4000mV, 40V, 400V, 600V
Resolution: 0.1mV
Accuracy: ±(0.5% rdg + 2 dgt)
Input impedance: 3MΩ on V inputs
10MΩ on mV input
Overload protection: 600V DC or AC rms
Transient protection: 6kV for 10μ sec
DC Current (50Hz - 60Hz)
Ranges: 40A, 300A
Resolution: 0.01A
DC Accuracy: ±(3.0% rdg + 10 dgts) 0 ~ 300A / 50 ~ 60Hz
Voltage burden: 1V
Overload protection: 500V DC or AC rms
Ranges: 400Ω, 4kΩ, 40kΩ, 400kΩ, 4MΩ, 40MΩ
Resolution: 0.1Ω
Accuracy: ±(1.2% rdg + 4 dgts) on 400Ω to
400kΩ ranges
±(1.5% rdg + 4 dgts) on 4MΩ range
±(3.0% rdg + 5 dgts) on 40MΩ range
Open Circuit volts: -0.45VDC typical, (-1.2VDC on 400Ω range)
Overload protection: 500VDC or AC rms
Ranges: -30 to 1000°F (-35 to 600°C)
Resolution: 0.1°
Accuracy: ±1°F (32 to 120°F)
±1% + 1.5°F (-4 to 750°F)
±2% + 4°F (-30 to -4°F, 750 to1000°F)
±1°C (0 to 120°C),
±1% + 1°C (0 to 400°C)
±2% +3°C (-35 to 0°C, 400 to 600°C)
Sensor type: K-type thermocouple
Overload protection: 60 VDC or 30 VAC rms
Ranges: 400μA
Audible indication: Less than 25Ω
Response time: 500ms
Overload protection: 500VDC or AC rms
Green LED will be on continuously
Range: 4μF, 40μF, 400μF, 4mF
1mF = 1000μF
i.e: 1.425mF = 1425μF
Resolution: 1nF
Accuracy: ±(3% rdg + 10 dgts) on 4μF range
±(3% rdg + 5 dgts) on 40μF to 400μF ranges
±(5% rdg + 20 dgts) on 4mF range
Input protection: 500VDC or AC rms
Hi-V(voltage) warning: <30VAC/DC meter beeps, red LED blinks.
Non-contact voltage Senses voltage 24V to 600V AC (50Hz to 60Hz) beeper chirps and big bright red LED comes on, works when meter dial is on any range.
Physical Specifications
Display LCD with a maximum reading of 4000
Data Hold Operating on all ranges
Range(RNG) Operating on all autoranges
Overrange "OL" mark indication
APO (Auto Power Off) Approximately 10 minutes
Measurement rate 2 times per second, nominal
Operating environment 32°F (0°C) to 122°F (50°C) at <70% R.H.
Storage environment -4°F (-20°C) to 140°F (60°C), 0 to 80% R.H. with battery removed
Accuracy Specifications good in ambient conditions of 73°F ±9°F (23°C ±5°) , >75% relative humidity
Temperature Coefficient 0.1 × (specified accuracy) per °F/°C; 32 to 66°F (0 to 19°C); 82 to 122°F (28 to 50°C).
Altitude 6561.7 Feet (2000 meters)
Jaw opening capability 38mm conductor
Power Single standard 9-volt battery, NEDA 1604, JIS 006P, IEC 6F22
Battery life 100 hours carbon zinc, 200 hours typical alkaline
Safety Designed to meet IEC/EN61010-1 and IEC/EN61010- 2-032, CATIII 600V, class II and pollution degree 2, indoor use comply with CE. C-Tick.
Ordering Information
Model Description Buy Online Price
SC77  Fieldpiece SC77 True RMS HVAC/R Clamp Meter Discontinued
See: SC640
Included Accessories
  • 1 - Wrap Tab K-Type Thermocouple (ATB1)
  • 1 - Silicone Test Leads (ASLS2)
  • 1 - Large Single Meter Case (ANC7)
  • 1 - 9-Volt battery (installed)
  • 1 - Operator's manual
Optional Accessories
ANC1 Fieldpiece ANC1 4 Pocket Deluxe Meter Case Buy Now $18.00
ANC3 Fieldpiece ANC3 Large Briefcase-Style Instrument Bag Buy Now Sale $63.20
(Reg. $79.00)
ANC5 Fieldpiece ANC5 Mail Pouch-Style Meter Case Buy Now $11.00
ANC7 Fieldpiece ANC7 Large Single Meter Case Buy Now $10.00
ANC8 Fieldpiece ANC8 Large Deluxe Meter Case Buy Now $36.00
ANC9 Fieldpiece ANC9 Wireless Refrigerant Scale Case Buy Now $20.00