The DIN-rail mounted zener diode barrier MTL7728+ (brand MTL, part of the EATON group) is designed for use in intrinsically safe (I.S.) hazardous zones. With two channels, the maximum zener‐diode voltage is 28 V, the minimum terminating resistor is 300 Ω and the maximum short‐circuit current is 93 mA. The barrier ensures that insufficient energy reaches the hazardous area to ignite an explosive atmosphere. Easy to install on standard DIN rail, features removable terminals and supports up to 2 zones. Compatible with I.S. devices such as conventional fire detection system detectors.
The MTL7728+ zener diode barrier is a 2-channel, 28 V, 300 Ω safety device designed for use in intrinsically safe (I.S.) hazardous areas. Manufactured by MTL (EATON group), it limits voltage and current to ensure that insufficient energy reaches the hazardous zone to ignite an explosive atmosphere. It is DIN-rail mountable, with removable terminals for fast installation and maintenance.
The MTL7728+ barrier provides passive energy limitation – zener diodes restrict voltage while a terminating resistor limits current. In the event of a fault on the safe side, this combination ensures the hazardous area remains within safe energy limits. With no active electronics, the barrier offers exceptional reliability and stability even under demanding conditions.
| Parameter | Value |
|---|---|
| Number of channels | 2 channels |
| Maximum zener voltage | 28 V |
| Minimum terminating resistor | 300 Ω |
| Maximum short-circuit current | 93 mA |
| Maximum end-to-end resistance | 333 Ω |
| Working voltage (Vwkg) | 25.9 V |
| Maximum voltage (Vmax) | 26.5 V |
| Operating temperature | -20 °C ... +60 °C |
| Storage temperature | -40 °C ... +80 °C |
| Mounting | 35 mm DIN rail |
| Earthing | Via DIN rail |
The barrier is mounted on a 35 mm DIN rail providing both secure mechanical fixing and grounding. Removable terminals simplify installation and servicing. The MTL7728+ is compatible with a wide range of industrial devices, signal transmitters, and detectors located in intrinsically safe zones.
Data sheet
The DIN-rail mounted zener diode barrier MTL7728+ (brand MTL, part of the EATON group) is designed for use in intrinsically safe (I.S.) hazardous zones. With two channels, the maximum zener‐diode voltage is 28 V, the minimum terminating resistor is 300 Ω and the maximum short‐circuit current is 93 mA. The barrier ensures that insufficient energy reaches the hazardous area to ignite an explosive atmosphere. Easy to install on standard DIN rail, features removable terminals and supports up to 2 zones. Compatible with I.S. devices such as conventional fire detection system detectors.
