DEHNguard ME/SE DC ... (FM)
Modular combined arrester / surge arrester for DC
- Universal combined arrester / surge arrester consisting of a base part and a plug-in protection module
- Device concept specifically developed for use in d.c. circuits
- Powerful d.c. switching device DCD prevents fire damage caused by d.c. switching arcs
- Use without additional backup fuse in defined applications
- Operating state / fault indication by green / red indicator flag in the inspection window
- Easy replacement of protection modules without tools due to module locking system with module release button
DEHNguard SE DC ...: Single-pole, modular surge arrester for d.c. application
DEHNguard SE DC ... FM: With remote signalling contact for monitoring device (floating changeover contact)
When developing this device series for protecting d.c. systems, the main focus was on the increased requirements of d.c. applications with regard to device safety in all operating states. The extremely powerful d.c. switching device DCD, which prevents fire damage caused by switching arcs, is the core of the DEHNguard SE DC devices.
DEHNguard SE DC … (FM) is, in the corresponding voltages, coordinated with DEHNsecure … (FM) type 1 lightning current arresters.
The DEHNguard SE DC devices combine high performance and ease of use in a single device. Their electrical parameters are rated for the most stringent requirements within lightning and surge protection systems. The high number of features shows that the main focus is both on reliable surge protection and device safety.
Proven heavy-duty varistors are used to discharge high impulse currents and limit the destructive surge impulses to the specified voltage protection level values. The operating state of the arrester is permanently monitored via the surface temperature of the heavy-duty varistor and the d.c. switching device DCD is immediately activated in case of overload. The mechanical visual indicator with green and red indicator flags, which is available for each protective path, is directly connected to the d.c. switching device DCD. When the red indication appears in the inspection window, the d.c. switching device DCD has already safely interrupted the d.c. switching arc and thus reliably prevented fire damage. In case of the DEHNguard SE DC … FM version, the arrester status can be additionally indicated via a three-pole remote signalling terminal.
The special design of the d.c. switching device DCD even ensures a short-circuit withstand capability up to 300 A d.c. – without arrester backup fuse (!). In combination with the specified backup fuses, the short-circuit withstand capability can be even increased to 25,000 A d.c., which is certainly an innovation in the field of d.c. applications.
The single-pole devices are available for voltages from 60 V to 900 V d.c. and thus DEHNguard SE DC surge arresters type 2 can be used for a variety of applications such as emergency power supply systems, d.c. systems for direct supply of d.c. drives, control circuits and battery-operated supply systems of any kind.
To implement these numerous features, the devices incorporate the modular Red/Line family design with a width of 1.5 modules. The mechanical design of the connection points is another safety feature. The covered screws provide additional shock protection and the projections for easily and safely entering the cable increase clearances and creepage distances so that no distance to other equipment must be maintained even in case of voltages up to 900 V d.c.
The coded plug-in protection modules ensure a high degree of protection. Consequently, damage caused by installing an incorrect module can be virtually excluded.
The universal T1 + T2 combined arrester is specially designed for use in case of current sources up to 950 V.