Digital A/C Line Monitor

Digital A/C Line Monitor
Item# 30-M20020
Regular price: $72.26
Sale price: $68.65
Availability: Usually ships the next business day

Product Description

Digital A/C Line Monitors

RMS voltage reading. Outlet surge voltage protection. Easy to read backlit LCD. Plugs directly into 3-pole outlet. Reads inverters accurately. Reads frequency (in Hertz). Easy 1-button interface to switch between readings. High and low voltage and frequency momentary audible alarms. Wiring alarms for incorrect polarity or bad ground.

For your personal safety and appliance protection, do not overlook this simple solution. The Digital Monitor M20020 constantly monitors voltage and frequency and also provides surge suppression. It also indicates potential shock hazards due to improper polarity and ground wiring. High or low voltage can damage your air conditioner, and other appliances.

This compact, easy to use instrument is made with advanced microelectronics and provides accurate testing and monitoring of electrical outlets and systems. Its small size and rugged construction allows for convenient installation in an electrical outlet or use as a portable service tool.

The voltage is measured as RMS which is much more precise than AC average or RMS estimation. RMS metering is the only method that can accurately measure all AC power sources. The RMS voltage and frequency readings are ideal for monitoring modified sine waves, such as solid-state generators, inverters, and Uninterruptible Power Supply (UPS) products.

The Digital Monitor display will alternate between line voltage in RMS volts and line frequency in Hertz. The LCD display shows an "F" in front of the reading to denote frequency. There are three display modes available: Alternating Voltage and Frequency (VOLT/FREQ.) Voltage only (VOLTAGE) Frequency only (FREQUENCY) Pressing the MODE button on the front of the Digital Monitor will cycle through the display modes. Both voltage and frequency are constantly monitored regardless of the display mode.

When the Digital Monitor detects a fault condition the fault LED comes on immediately upon fault threshold being exceeded. If the fault threshold is exceeded and sustained for three seconds it sounds an audible alert for 5 seconds and shows the cause for the fault on the display. The wiring faults are Ground Fault (GF) and Polarity Fault (PF). The voltage faults are Low voltage (LO) of 102 Vac or lower and High voltage (HI) of 135 Vac or higher. The frequency faults are Low Frequency (LF) of less than 55 Hz and High Frequency (HF) of over 65 Hz. Fault reset thresholds must be obtained to re-enable the fault alarms. When a wiring fault (GF or PF) is displayed, the MODE button may be used to sequence the display to show the current voltage or frequency by successive button actuations.

The surge protection (or transient suppression) on the input source lines protects other devices on the same circuit by absorbing surges up to 300 joules.

Specifications: Minimum Typical Maximum

Operating Temperature 0C 60C

Storage Temperature -45C 85C

Voltage Range 85 VAC RMS 120 VAC RMS 150 VAC RMS

Frequency Range 40 Hz 60 Hz 80 Hz

Current 0.02 Amps

Surge Suppression 300 Joules

Under-voltage Alarm 102 VAC RMS

Over-voltage Alarm 135 VAC RMS

Under-Frequency Alarm 55 Hz

Over-Frequency Alarm 65 Hz

Have a Question?Email me at or give me a call during regular business hours (Eastern Time) at 330-556-5080 or Toll Free (844)9RV-PART (978-7278) Thanks.. Dan