Monsol specialises in the design, development and manufacturing of hardware and software for monitoring photovoltaic installations. We are currently expanding our range of devices for individual monitoring of photovoltaic panel strings for the purpose of achieving the greatest accuracy in monitoring and not obstructing the flow of current in order to simplify the installation and guarantee better performance in the installation.

Thanks to its new design, the new Monsol 1000/1500V String Monitor, especially designed for monitoring photovoltaic plant strings, features innovative metering and manufacturing technology, which reduces costs in terms of both space and installation.

The new Monsol 1000/1500V String Monitor is the result of 6 previous devices designed and 10 years of experience and research in monitoring strings of photovoltaic plants.

CE/UL Certification


The new Monsol 1000/1500V String Monitor measures current in photovoltaic plant strings up to 1,500 V DC.

Measurement of strings in the positive as well as the negative pole.

Its configuration, based on a modular device, can monitor from 8 string inputs up to a maximum of 64 individual strings.

Measurement of busbar voltages of up to 1500V DC thanks to its Monsol 1500 Volt® expansion module.

Installation of a weather station (sensors of photovoltaic radiation, ambient temperature, panel temperature, etc.) thanks to the Monsol Meteo® expansion module.


The Monsol 1000/1500V String Monitor is built on a PCB manufactured with unique technology, patented worldwide, which allows for the manufacturing of metering equipment for high-energy voltages with the greatest accuracy.

The new Monsol 1000/1500V monitoring system is subjected to exhaustive control and quality tests, showing itself to be a robust and reliable device.

It complies with American (UL) and European (CE) regulations.


In addition to monitoring direct current, the Monsol 1000/1500V String Monitor allows for monitoring analogue and digital signals through different inputs included for that purpose. The device features an internal communication system, which allows for self-detecting the expansion modules connected to it.

The communication protocol implemented in the Monsol 1000/1500V String Monitor is the industrial standard ModbusRTU (under RS485). Thanks to the use of this open communications standard, the new device features simplicity, robustness and adaptability to industrial environments and systems.


In addition to the unique properties of the PCB used in the manufacturing of the new Monsol 1000/1500V String Monitor, it features the most accurate current sensor in the market. The current sensor takes readings using the highly accurate Hall effect.

It has an operating range from -40℃ to +80℃.

  • Up to 32 channels per device (1 master + 3 slaves)
  • 30 A per channel
  • Unobtrusive monitoring based on the Hall effect
  • Margin of error of ±1% (14 bits)
  • Compatible with 1000V and 1500V DC strings
  • Up to 60 readings per minute
  • 2 isolated digital inputs of the open/closed contact type
  • 1 input for a PT100 temperature sensor
  • RS485 communications port:
    • Standard Modbus RTU protocol
    • 3kV insulation
    • Surge protection
    • Transitional voltage protection
  • Modbus microswitch addressing
  • Power and communication indicator LEDs
  • 24V dc ±10V Input with 3kV insolation
    • Surge protection
    • Transitional voltage protection
    • Polarity inverter protection
  • Industrial operating temperature range of -40℃ to +80℃.
  • PCB thickness of 2 mm, appropriate for industrial handling
  • Innovative high-current manufacturing technology
  • Current busbar of up to 240 A without external conductor (copper strip)
  • Finish in chemical gold bath for maximum conductivity
  • Automatic detection of extensions
  • 2-year guarantee
  • Optional overmoulding in epoxy resin
  • Extensions:
    • Monsol Meteo® extension with inputs to install weather sensors
    • Monsol 1500 Volt® extension for monitoring voltages up to 1500V DC
Certifications and approvals

Module Monsol 1500 Volt ® designed for the monitoring of string busbar voltage must be connected to the last string monitor through a 4-wire cable. It must always be the last module in the system.

Voltage monitoring module Monsol 1500 Volt ® is not compatible with the high-precision module Monsol Meteo ® for the monitoring of analogue signals.

Monsol 1500 Volt ®  obtains the individual voltage of each box and compares the voltage drop in the string box with the input voltage of the inverter. The margin of error is +/-1%.

Certified combiner box manufacturers
3D Models

3D Model – Monsol 1000/1500 Shunt