Extech Instruments PM120 User Manual

USER MANUAL
PM120 – Power Monitor
Introduction
Thank you for selecting the Extech PM120 Power Meter. The PM120
monitors and records power usage of home and work appliances for
energy conservation and cost reduction analysis. The power meter
measures the voltage, current, power, and power factor as well as total
time, cost, and energy. The PM120 is equipped with a high‐precision
current sensor giving real‐time monitoring of AC power supply units. It
features an alarm and power cut‐off for safety.
This device is shipped fully tested and calibrated and, with proper use,
will provide years of reliable service. Please visit our website
(www.extech.com) to check for the latest version and translations of this
User Manual, Product Updates, Product Registration, and Customer
Support.
Features

Large dual LCD manually displays electrical, cost, and metering
functions in real‐time.

Electrical safety transfer function when connecting this product to
a socket and then plugging the electrical appliance into this
product.

Over‐current warning function.

Primary LCD shows voltage, current, power, power factor, or
frequency.

Secondary display shows total time, cost, set, or energy.

Enter electric charge (cost setting) to calculate and display kWh.

Display cost of operation in minute, hour, day, and week.

Battery backup stores data when removed from outlet.

Three prong standard US plug and front socket for easy connection.
1
Safety Information
To ensure the safe operation and service of the meter, follow these
instructions closely. Failure to observe warnings can result in severe
injury.
WARNINGS
WARNINGS identify hazardous conditions and actions that could
cause BODILY HARM or DEATH.

Check the housing for cracks or missing plastic especially
surrounding the plug. Do not use if any part of the meter is
damaged.

Verify the meter's operation. Do not use if the meter responds
abnormally as the internal structure may be damaged.

Use the meter only as specified in this User Guide or
accompanying Quick Start to avoid compromising the protections
provided by the meter.

Do not exceed the rated power or current of this meter.

Do not expose the meter to extremes in temperature or to high
humidity.

Keep this meter away from children.

Do not use the meter in the presence of explosive gas, vapor or
dust.

To reduce risk of fire or electric shock, do not use the meter if it is
wet and do not expose the meter to moisture.
Meter Description
1. Primary Display: See ↑M
for functions.
2. Secondary Display: See ↓M
1
for functions
2
3. ↓M: Cycles through
secondary display functions:
Total Time, Cost, Energy and
3
the corresponding values of
4
each selection.
4. ↑M: Cycles through
primary display functions:
Voltage, Current, Power,
5
Power Factor, Frequency
and the corresponding
values of each selection.
5. Appliance outlet
6. SET: Long press to set the
cost in $/kWh
7. +/RESET: Short press to increase the digits. Long press to
reset the Energy or Cost functions. Short press to wake the
power monitor from sleep mode.
Operation
Measurement
Plug the PM120 into a household socket to being measuring. The
display will power on and enter default measurement display
(Voltage and Total Time).
Select the Mode
 Short press the ↑M button to scroll through primary display
functions. The meter will cycle through Voltage, Current,
Power, Power Factor and Frequency. Long press ↑M to return
to default 'Voltage' mode.
 Short press the ↓M button to scroll through secondary
display functions. The meter will cycle through Total Time,
Cost, and Energy. Long press ↓M to return to default 'Total
Time' mode.
Total Time
Check the time by pressing the +/RESET button. If the
accumulated time is less than 1 day, only Hour and Min will
display. If the accumulated time exceeds 1 day, the LCD will only
display 'Day'. To view the hour and minute display, short press
the +/RESET button.
7
6
Total Time in Days
Note: If the meter is above the rated current, the display will
show a warning in the primary display and OL in the secondary
display. Both displays and the power light will flash.
Warning Icon and Overload
PM120‐en‐US_V1.0 8/17
Total Time in Hour:Min Total Time since power ON
Power OFF