SMS-controlled power cycling, temperature monitoring and mains failure alerting — completely independent of internet connectivity. A 30-second SMS command instead of a multi-hour site visit.
How do you recover a remote device when it has lost internet connectivity and can no longer be managed remotely?
The PowerTXT provides a completely independent control path using SMS messages. This means that even when a router, CCTV system, network switch, computer or industrial controller has completely lost internet connectivity, the equipment can often still be power-cycled remotely.
This is not a device we have simply read about. We have personally tested the PowerTXT and have live customers successfully using it in production environments.
How It Works
The PowerTXT combines a GSM modem, SMS command processing, a controllable mains relay, temperature monitoring and mains failure monitoring within a single device. An authorised user sends an SMS message. The device processes the command and performs the requested action.
Once the command has been executed, the device sends an acknowledgement SMS confirming the action taken. Because SMS operates independently of internet connectivity, the device can remain controllable even when the equipment connected to it has completely lost network access.
Commands include: Turn power ON, Turn power OFF, Reboot connected equipment.
Works via SMS — completely independent of internet connectivity.
Power is cut, restored, or cycled according to the command received.
The device confirms the action taken — typical responses include "Mains ON" or "Mains OFF".
Capabilities at a Glance
Hard reboot any connected device without visiting site — routers, switches, CCTV, servers.
Programmable thresholds generate automatic SMS alerts when conditions move outside limits.
Detects a power outage and transmits an alert via internal reserve energy — even after losing mains.
Only pre-approved telephone numbers can issue commands — or send commands via the KeySIM platform.
Compatible with KeySIM SMS platform. SMS commands can be sent directly from the KeySIM management platform rather than from individual mobile phones, with acknowledgements returned to authorised destinations.
Features in Detail
Remote Equipment Reboot
If a device becomes unresponsive, an engineer can send an SMS command to disconnect power. Once the equipment has powered down, a second command restores power — performing a hard reboot without requiring anybody to attend site.
For remote locations, this can dramatically reduce downtime and eliminate unnecessary engineering visits. One of the most common applications is recovering Teltonika routers, CCTV systems, NVRs, network switches, BMS units and industrial controllers.
Temperature Monitoring
Temperature thresholds can be programmed into the device, allowing it to automatically generate SMS alerts when environmental conditions move outside predefined limits.
This makes the PowerTXT function as both a remote power controller and an environmental monitoring platform — enabling engineers to identify developing problems before they result in equipment failures.
Alerts generated for:
Mains Failure Monitoring
In our view, the most technically impressive feature. Most monitoring devices lose power at exactly the same moment that the mains supply fails — if the device itself has lost power, how can it possibly send an alert?
The PowerTXT overcomes this by maintaining sufficient internal reserve energy to continue operating for a short period after mains loss. When the power outage occurs, the device detects it, the GSM modem transmits an SMS alert, and it remains operational long enough for successful message delivery.
The result is a genuine mains failure notification from the same device that has just lost its own power source.
Security
The PowerTXT can be configured so that only authorised telephone numbers are permitted to issue commands. SMS messages received from unauthorised numbers are ignored — random users cannot control connected equipment.
For KeySIM customers, SMS commands can be sent directly from the KeySIM management platform rather than individual mobile phones, creating a controlled environment with commands originating from authorised sources and acknowledgements returned to authorised destinations.
For organisations operating critical national infrastructure or defence-grade environments, it is even possible to disable SMS services entirely at SIM level through the KeySIM platform, enabling them only at the exact moment a legitimate command needs to be sent.
Why SMS Still Matters
Many modern monitoring systems focus entirely on IP connectivity. But SMS remains one of the most resilient communication methods available.
This independence from the primary communications infrastructure is one of the reasons the PowerTXT remains so effective. It provides a completely separate control path that remains available even when the primary network has failed.
Applications
The PowerTXT is designed for organisations operating remote infrastructure where connectivity failures are common and site visits are expensive. For remote locations, the difference between a 30-second SMS command and a multi-hour site visit can mean the difference between minimal downtime and a full-day outage.
Combined with a KeySIM IoT SIM card, it becomes a highly resilient out-of-band management platform capable of maintaining control even when traditional internet connectivity has completely failed.
Common PowerTXT deployments:
Current UK PowerTXT devices operate using SMS messaging. Historically these devices have been deployed using GSM-based services. At the time of writing, Vodafone and EE continue to support 2G services whilst O2 no longer supports traditional 2G voice services for roaming partners and Three has historically not supported traditional roaming voice for this type of deployment.
EE intends to begin retiring its 2G network from May 2029 and Vodafone intends to retire its UK 2G network during 2030. For current deployments, the PowerTXT remains an extremely capable and widely deployed remote management solution with a substantial operational lifespan ahead of it. Organisations planning very long-term deployments should be aware of the industry's longer-term direction towards newer technologies.
Related Resources
Contact our team to discuss the PowerTXT alongside KeySIM IoT SIM connectivity for your remote infrastructure management requirements.