Loopback Systems Inc. QLog™


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QLog™ is a battery-powered or solar-powered field ready IoT based data logging system that provides paperless recording for continuous water quality monitoring of CT (contact time) for free or combined chlorine, PH and temperature. This system records months of data which is archived in a CSV file that can be retrieved remotely from any PC, smart phone, or smart tablet.

The system comes with a friendly cloud interface that allows you to log in and view your remote analytical assets at any time. The dashboard provides you with a view & trending of your remote analytical measurements. You may also set key Hi or Low alarm points on your measurements that can easily notify the operator by way of text or email if a critical condition exists.

The base system comes standard with three (3) analog inputs and three (3) digital inputs. The digital inputs can detect on/off status or frequencies up to 2kHz. The analog inputs can be set to 1-5Vdc, or 4-20mA powered by the built-in battery pack.

The QLog™ includes our 3+3 dashboard, which includes 3 years of historical trends and 3 years of Verizon Cell/Dashboard service. There is no programming necessary to retrieve the data from QLog. Simply log into your account and your data will immediately show up on your personal dashboard. From there, you can assign users that will receive alarms based on the measurement of the sensors.

QLog™ is also available with a complete sensor and sample system for your chlorine measurement applications.

Contact us today for more information.

Features & Applications


  • Three (3) analog inputs, three (3) digital inputs, and one (1) relay
  • LTE CAT M1 connectivity optimized for low data usage
  • Integrated Active/passive  inputs/output for multi-sensors
  • Integrated inputs/output for multi-sensors
  • Data location from built-in GPS
  • SignalFire cloud monitoring/alarming service
  • Powers sensors from battery or external solar
  • Now certified by Verizon!


Water Systems

  • Well House
  • Booster Station
  • Water Tank
  • Distribution System Endpoints
  • Reservoir Monitoring

Wastewater Collection Systems

  • Final Filtration
  • Plant Effluent

Technical Specifications

  • Operating Temp: -40 to +185°F (-40°C to 85°C)
  • Humidity: 0% – 100% condensing
  • Power: Four (4) 3.6Vdc D side size Lithium Thionyl Chloride batteries
  • NEMA 4X Enclosure with wall mount brackets
  • Input/Output:• 3 Digital Inputs report state, total counts, and frequency (2kHz max)• 3 Analog Inputs (1-5Vdc or 4-20mA)
  • Data Interface: LTE CAT M1 MQTT w/ SparkPlug B
  • Cellular Radio Power: 23dBm
  • Antenna Type: LTE w/ Internal GPS
  • Attached Analog Sensor: Configurable 13Vdc or 18Vdc
  • Enclosure: Industrial polycarbonate UV Rated; IP64
  • Electrical Connection: Pluggable terminal block, 16-30AWG screw terminals
  • Local Micro-USB Configuration Port
  • Weight: 1 lbs (0.6kg)
  • Estimated Monthly Data Usage:Check-in interval dependent• 30 sec = 54 MB• 1 min = 27 MB• 5 min = 5.4 MB• 15 min = 1.08 MB• 60 min = 0.27 MB

Video & Diagrams

SignalFire Ranger – From Sensor to Cloud

Data Sheet