Inside a cold room: frosted racks with boxes, a ceiling evaporator, a temperature/humidity sensor on the wall and the heavy insulated door
SOLUTIONS · COLD STORAGE

Cold Storage Temperature Monitoring: From Alarms to Records

Cold rooms tend to fail when no one is watching. Using the three moments when things most often go wrong, this article shows how temperature sensing, the door and record-keeping come together in one system that raises its own alarms and keeps its own log.

Published
THREE MOMENTS

Three moments when cold rooms go wrong

Each clip shows a common pain point and how it is solved once our monitoring system is in place.

Over-temperature at night, and no one knows

BEFORE

With no one on the night shift, a temperature problem or an urgent settings change means someone has to go on site, and often nobody notices until the next morning.

AFTER

If the temperature stays above the limit for longer than the set time, your phone is notified and the on-site siren sounds.

A door left ajar, and no one notices

BEFORE

Cold air leaks through the gap and the temperature creeps up slowly, so it usually goes unnoticed until the room is already too warm.

AFTER

A timer starts as soon as the door opens. If it stays open past the set time, the alarm sounds before the temperature starts to rise.

The network drops, the log keeps going

BEFORE

When records only exist once they reach the network, every outage leaves a gap.

AFTER

The device logs data in real time and keeps recording through network outages; the full log can be exported once the connection is back.

ARCHITECTURE

System architecture and devices

Behind all three moments is one system: the sensor and door contact send in their signals, the RIO I/O controller receives them and handles the control signals, and CGate keeps a long-term log and passes the data on to the monitoring PC and phone.

Cold storage monitoring architecture: the temperature/humidity sensor connects over Modbus, and the door contact and siren through RIO, to CGate, which links to a monitoring PC over the network
Temperature & humidity sensorModbus RTU/TCP
Door contactOpen/closed signal wired to RIO DI
On-site sirenLight-and-sound alarm driven by RIO DO
RIO Expandable I/O Module ControllerA DI module reads the door contact and a DO module drives the siren; built-in logic handles timed control
CGateKeeps a continuous log, forwards data and provides the user interface
Monitoring PCLive values and logs over the network; email alerts

CGate

Keeps a continuous log, forwards data and provides the user interface

Modbus (sensor, RIO → CGate)
I/O signals (door contact DI, siren DO)
Network (CGate → monitoring PC)

CGate

GATEWAY
  • Reads Modbus RTU/TCP sensors
  • Alarms can require a minimum duration
  • Built-in, exportable log that keeps recording offline
View CGate products

RIO

REMOTE I/O
  • DI: door contact open/closed signal
  • DO: drives the on-site siren
  • AI: sensors with current/voltage output
  • Built-in DDC programs for real-time logic control
  • Sends events to CGate over Modbus for logging and alerts
View RIO products

4G connectivity

OPTION
  • No wired network on site? Notifications go over cellular
  • Optional on CGate-05/06
FAQ

Questions before you start

A cold room door with the temperature monitoring panel on the wall beside it

Can an existing cold room be retrofitted?

Yes. Just add sensors and a gateway to the existing room; there is no need to rebuild it.

What kinds of sites is it suited to?

Chilled rooms, freezers and cold-chain warehouses. Whether you have one room or several, the Gateway and RIO setup is planned around the number of sensing points.

Which sensors can be connected?

Standard Modbus RTU/TCP sensors connect directly; points are set up from the sensor’s register map. Sensors with analog (current/voltage) output connect through a RIO AI module.

Can alerts go to LINE?

Built-in notifications go out by email. LINE can be set up to your requirements, including what each message contains.

What if the network goes down?

Recording continues on site, and the full log can be exported once the network is back. Sites without a wired network can add the 4G option.

TAILORED TO YOUR SITE

Every cold room is different

Sensor types, alarm conditions and notification methods (such as LINE) can all be customized to your site. Tell us about your cold room and our sales team will help you plan it.

Contact us