When a Packaging Line Needed More I/O Without a Bigger Panel
A system integrator was upgrading a small packaging line. The existing controller had run out of inputs, and the panel had no room for a larger unit. The answer was the Schneider TM221C24R, a Modicon series controller that packs 14 digital inputs, 10 relay-type digital outputs, and 2 analog inputs into a DIN rail housing just 130 mm long and 95 mm wide.
This compact controller runs on 24 V DC and handles mixed signal types without extra modules. That made it a direct fit for the integrator’s space and wiring constraints.
What the TM221C24R Delivers
The TM221C24R is a Modicon controller from Schneider Electric. It combines digital and analog I/O with a 32-bit processor running at 22 ns per instruction. Program memory is 256 kB, and 64 kB of retention memory keeps critical data safe through power cycles. A built-in real-time clock supports time-sensitive tasks such as scheduling and event logging.
Relay-type outputs give you direct switching of devices that draw more current than solid-state outputs allow. The two analog inputs accept 0-10V signals, so you can read sensors like pressure transmitters or position feedback devices without adding an analog module.
Technical Specifications at a Glance
| Specification | Value |
|---|---|
| Manufacturer | Schneider Electric |
| Product Line | Modicon |
| Part Number | TM221C24R |
| Power Supply Voltage | 24 V DC |
| Digital Inputs | 14 |
| Digital Outputs | 10 (Relay Type) |
| Analog Inputs | 2 (0-10V) |
| Processor | 32-bit |
| Processing Speed | 22 ns per instruction |
| Program Memory | 256 kB |
| Retention Memory | 64 kB |
| Real Time Clock | Built-in |
| Operating Temperature | -10°C to 55°C |
| Mounting | DIN Rail |
| Dimensions (L x W) | 130 mm x 95 mm |
| Weight | 0.45 kg |
Where This Controller Fits Best
Small Machine Control
With 14 digital inputs, the TM221C24R reads signals from proximity sensors, limit switches, and pushbuttons on compact machines. The 10 relay outputs drive contactors, solenoid valves, and indicator lamps directly.
Analog Monitoring in Tight Spaces
Two 0-10V analog inputs let you monitor pressure, temperature, or position without a separate analog card. This saves panel space and reduces wiring time.
Upgrade Path for Legacy Panels
When an older controller fails, the TM221C24R offers a DIN rail mount and compact footprint that often fits existing enclosures. The 24 V DC supply matches common industrial power, so you may not need a new power supply.
Installation Notes
Mount the controller on a standard DIN rail inside a control panel. Keep the unit within the operating temperature range of -10°C to 55°C. Allow airflow around the enclosure. Wire the 24 V DC supply according to your panel’s electrical drawings. Connect digital inputs to sensors and switches, and wire relay outputs to the loads they control. Route analog input wiring away from high-voltage cables to reduce noise on the 0-10V signals.
Reliability and Maintenance
The TM221C24R has no moving parts, so wear is minimal. Check terminal connections periodically for tightness. Inspect the panel for dust buildup that could block airflow. Verify the real-time clock battery if your application depends on time-based functions. In high-temperature environments, confirm the panel stays within the rated range. These simple steps help you avoid unplanned downtime.
Compatibility and Expansion
The controller supports additional I/O modules when your application grows. This lets you start with the built-in 14 inputs and 10 outputs, then expand as needed. The 256 kB program memory and 64 kB retention memory give you room for logic and data storage. The built-in real-time clock works with time-based control sequences.
What to Verify Before You Buy
Confirm that 24 V DC is available in your panel. Check that 14 digital inputs and 10 relay outputs cover your I/O count. If you need analog signals, verify your sensors output 0-10V. Measure your DIN rail space to ensure the 130 mm x 95 mm housing fits. For current lifecycle status and availability, contact SpareTechPLC before ordering.
Frequently Asked Questions
How many I/O points does the TM221C24R have?
It provides 14 digital inputs, 10 relay-type digital outputs, and 2 analog inputs rated for 0-10V.
What power supply does this controller need?
The TM221C24R operates on 24 V DC.
Can I expand the I/O on this Modicon controller?
Yes. The controller supports additional I/O modules for more points.
What is the operating temperature range?
It operates from -10°C to 55°C.
Does it have a real-time clock?
Yes, a real-time clock is built in for time-sensitive tasks.
