Keywords: voltage, meters, sensors, AC, DC, VAC, VDC, detectors,
Quick guide to voltage meters and detectors.
Monnit sells a variety of AC (Alternating Current) and DC (Direct Current) meters. AC currents repeatedly change direction. DC currents flow in one direction. Most digital electronics use a Direct Current, while homes are typically wired with an Alternating Current. This means that if you plan on using a meter to monitor the voltage in a wall socket, it must be a VAC unit. Monnit encourages you to check the owner’s manual and research the type of current used, for the safe operation of the voltage meters used.
Monnit wireless voltage meters measure the voltage between two electrical points by connecting the leads on the sensor to the positive and ground terminals of the equipment being monitored. The right product for you will depend on the output voltage level of the appliance you are monitoring. A voltage meter can be connected to any kind of variable voltage appliance, such as a transducer or sensor that outputs voltage. Anything over 10 milliamps (0.01 amp) can produce a severe shock, so take great care in operating these devices.
Sensor |
Accuracy |
User Calibrated Accuracy |
Max Rated Input |
Resolution |
Voltage Range |
Applications |
Direct Current (DC) Meters |
||||||
0-1 VDC Meter |
+/- 1.5% |
+/- 1.5% |
5 Volts DC |
~ 0.6 mV |
0 – 1 Volts DC |
Appliance Monitoring |
0-5 VDC Meter |
+/- 3% |
+/- 0.5% |
10 Volts DC |
~3 mV |
0 – 5 Volts DC |
Voltage Measurement |
0-10 VDC Meter |
+/- 3% |
+/- 0.5% |
20 Volts DC |
~5 mV |
0 – 10 Volts DC |
Battery Health |
0-50 VDC Meter |
+/- 3% |
+/- 1% |
75 Volts DC |
0.025 Volts DC |
0 – 50 Volts DC |
Electric Motors |
Direct Current (DC) Detectors |
||||||
50 VDC Detection |
+/- 3% |
+/- 1.5% |
50.0 Volts |
N/A |
0 – 50 Volts DC |
Battery Power |
Alternating Current (AC) Meters |
||||||
20 Amp AC Meter |
+/- 2% |
+/- 1% |
50 Amps RMS |
~.01 A rms |
0 – 20 A rms |
Amp Hour Meter |
150 Amp AC Meter |
+/- 2% |
+/- 1% |
200 Amps RMS |
~ 0.1 A rms |
0 – 150 A rms |
Current Monitoring |
AC / DC Meter |
||||||
0-500 VAC/VDC |
+/- 3% |
+/- 1.5% |
600 Volts AC/DC |
0.25 A rms 0.35 Volts DC |
0 – 500 Volts AC/DC |
Appliance Monitoring |
AC Detection |
||||||
4-500 VAC Detection |
+/- 1 VACrms |
+/- .5 VACrms |
600 Amps RMS |
0.25 A rms |
4 – 500 A rms |
Power supply monitoring |
mA Meter |
||||||
0-1mA (DC) |
0.7 mA |
0.05 mA |
1 mA Volts DC |
~0.01 mA (11 Bit single ended) |
0 - 1 mA |
Pressure sensor integration |
0-20mA (DC) Meter |
0.7 mA |
0.05 mA |
20 mA Volts DC |
~0.01 mA (11 Bit single ended) |
0 –20 Volts DC |
Current Transducer Monitoring |
The Wireless 0-1 VDC Voltage Meter can interface with other devices to measure voltage up to 1.2 VDC. By connecting the leads on the Monnit Wireless Voltage Meter to the positive and ground terminals of another device, battery or sensor, it can measure the voltage and send data to the iMonnit Online Sensor Monitoring and Notification System.
Wireless 0-5 VDC Meters measure the voltage between two electrically charged points. Transducers with a low direct current voltage output typically at or below 5 Volts are best for this meter. Passive devices require a supply of their excitation voltage to the device.
The Monnit Wireless 0-10 VDC Voltage Meter measures the voltage between two electrical points. It can be connected to the power and ground of any voltage source and measure within stated accuracy up to 10 VDC. The sensor can be connected to any kind of variable voltage device, such as a transducer or sensor that outputs voltage. If the device to be measured is passive, users must supply their excitation voltage to the device.
The Monnit Wireless 0-50 VDC Voltage Meter measures the voltage between two electrical points. It can be connected to the power and ground of any voltage source and
Monnit’s Wireless 50 DC Voltage Detection sensor detects the presence or absence of electricity. This device is intended for use on battery or other DC sources, up to 50 Volts. Not intended for use with AC Voltages, it is perfect for batteries, adapters, solar equipment, vehicles or machinery, and any other electrical appliance monitoring. The sensor triggers on voltage presence to voltage Absence and vice versa. The data is displayed as “Voltage Detected” or “No Voltage”.
The Wireless 20 Amp AC Current Meter measures the RMS (root mean squared) current of an alternating current. This is the low level of the three AC Meters available in Monnit’s ALTA series. The 20 Amp Meter clips onto the CT around only a single wire of the AC system (clipping around a hot and neutral wire at the same time will result in 0 current readings). The meter operates by using a current transformer (CT) that wraps around the “hot” wire of a two-wire (hot, common, ground(optional)) power system. Up-to-date reports on the RMS current are then transmitted to iMonnit, where the data can be evaluated.
Monnit’s Wireless 150 Amp AC Current Meter is responsible for monitoring the alternating current of a power system. This meter operates the same way as the 20 Amp above but is capable of measuring a much greater level of amp RMS. Clipping the meter around a wire connected to the AC system will deliver reports on the minimum RMS current, maximum RMS current, average RMS current, and amp hours to the iMonnit system.
The Wireless 500 VAC/VDC Voltage Meter is an analog measuring device reporting the measured voltage on user-specified intervals. There are three operating modes for this meter, which can be set by the user, from where you can obtain the voltage measurement in VAC, the peak voltage, or the DC voltage. The meter operates by connecting the leads on the Monnit Wireless 500 VAC/ VDC Voltage Meter to the hot(black) and neutral(white) terminals of another device, battery sensor, or power system it can measure the voltage and send data to iMonnit.
The Wireless 0-1 mA DC Current Meter is designed to work with the Flex-Core MCT5 current transducer that converts 5 Amps AC into a DC signal up to 1 mA. By connecting the leads of the Monnit wireless 0-1 mA current meter to the output of the Flex-Core MCT5 current transducer, the sensor wirelessly transmits data through a Monnit Gateway to the iMonnit Online Sensor Monitoring and Notification System.
Wireless 0-20 mA (milliamp) Current Meters measure the current of another device. While not technically a DC meter, this can be used to monitor applications with a low current output. With the meter connected between the positive and ground terminal of a separate appliance, real-time reports on the voltage level can be sent to iMonnit.