We’ve created a DIN rail mount industrial surge protector that works to provide protection of the electronics in your cabinet/panel or in tandem with the field surge protectors to provide end-to-end protection. The I/O-24 is designed to protect two loops or 4-wires and only takes up ½” of valuable DIN rail space. Ensure the safety of your electronic equipment and know that your devices and electronics are in good hands.

ZeroDT I/O-24

The I/O-24 is the perfect addition to any industrial facility that operates a number of electronic devices. Its specifications include:


  • Nominal Voltage: 24 Vdc
  • Maximum Continuous Operating Voltage: 36 Vdc
  • Protects two loops or 4-wires
  • Nominal Surge Current (able to withstand repeated applications):
    • 8/20 μs, Line-to-Ground: >1200 Amps
    • 10/1000 μs, Line-to-Ground: >130 Amps
  • 111 mm H, 12.6 mm W, 99 mm D
  • Mounts to Grounded DIN Rail
  • Compression lugs accept #26 to #14 AWG conductors

Ensure the Safety of Your Hardware Surges and Transients

You never know when disaster is going to strike. Whether it is from manmade events such as grid switching, motors, or another current switching, or natural events such as lightning, overvoltage transient surges can damage sensitive electronics. The overvoltage transient energy can damage or destroy your highly sensitive hardware. You are left with devices that no longer function and hefty costs to replace them, but more importantly, the job that hardware was doing is now shut down, and downtime impacts revenue.

When you implement our end-to-end surge protection devices, you can avoid these system downtimes. ZeroDT is a leading rail mount surge protector manufacturer that has created devices that offer ultimate protection. We’ve founded our brand by offering zero downtime with everything we do, hence the name ZeroDT.

Have peace of mind with unforeseen power surges and keep your devices protected from equipment failure. As part of our end-to-end protection, the ZeroDT I/O-24 offers the ultimate electrical cabinet/panel protection. Get started with this powerful DIN rail mounted surge protector device.

Take Advantage of SASD Benefits and Key Features

Unlike other surge protection technologies, the industrial grade SASD (Silicon Avalanche Suppression Diode) technology used by ZeroDT does not degrade with usage. This gives you the same level of protection five years from now as you had on the day the unit was installed. SASD technology also provides the response time you need to protect from events that are lightning-fast (literally lightning fast!) – no other technology is faster.

By installing the ZeroDT I/O-24 at that critical point where your field cables come into the cabinet/panel, it can provide the necessary protection for your electronics against any transient overvoltage energy coming back into the cabinet/panel from the field device cables. It’s designed in bidirectional capabilities that also protects your field devices against any surge leaving the cabinet/panel and damaging your field devices as well as eliminates installation direction mistakes seen with competitive units. The module top-mounted screw terminal compression lugs provide secure connections for #26 – #14 AWG conductors that are easy to get to.

With its UL listings for both ordinary locations as well as hazardous locations (Class 1, Division 2) and protection of two loops or 4-wires in only ½” of DIN rail space, the I/O-24 fits the requirements for new panel designs as well as changing out old competitive units that are degrading with each surge that comes down the line. The I/O-24 can be used with confidence on your analog measurement circuits (4-20 mA loops) or on digital communication such as CAN bus, HART protocol, Profibus, Modbus, RS-485, and dc power loops without hampering readings or communications in any way. It is essentially invisible to the circuit until an overvoltage transient event occurs, and then as soon as the voltage returns to normal, it returns to the original state – without degradation and ready for the next surge. With the ZeroDT I/O-24, you get the ultimate protection for your key electronics.

Enjoy End-to-End Surge Protection

There’s no need to worry about whether or not your devices are safe from transient overvoltages. Installing a field mount device at your measurement/process control device to protect it and mounting a DIN rail mounted protection device back at the cabinet/panel where the field cables enter will protect those electronics.  The ZeroDT I/O-24 is designed to provide protection that is fully bidirectional so mounting direction errors are eliminated, and to provide protection against transients coming into the electronics from the field as well as against overvoltages going out to the field devices.