Electricity + Control August 2017

ELECTRICAL PROTECTION + SAFETY

turing, the surge protective devices (SPDs) should take up as little space as possible. The goal is to centralise numerous service functions − such as system monitoring − in the control room. To oper- ate the system safely from an EMC perspective, SPDs are implemented in large systems. Protection in a confined space Numerous channels often have to be housed with- in a small area in order to transmit analogue or digital signals. Since space is becoming increas- ingly valuable, the narrowest components of this product range have a width of only 3,5 mm. The components of Termitrab complete are equipped with six terminal points to which two signal lines each and a common reference potential can be connected. With this extremely compact and narrow con- tactor, which is being made available on the world market for the first time, up to 572 signal lines can be protected on one metre of DIN rail (see Figure 2 ). The power dissipation has been mini- mised significantly as well, due to the decoupling resistors in the protective circuits. This feature also aims to satisfy the demand for installing more de- vices in increasingly smaller spaces. Figure 2: 572 signals per metre: With its extremely narrow components, Termitrab complete saves a great deal of space in the control cabinet. The lightning protection standards recommend regular inspection of protective devices. This is only possible through visual examination. The Ter- mitrab complete product range features a status indicator that displays an overload of the surge protection directly on the device. Since no addi- tional power is needed for this indicator, the pro- tective device also displays the fault continuously during an overload. If this information is displayed in a control room, the optionally available ‘remote signalling modules’ (see Figure 3 ) ensure the nec- essary data transmission. Either the PLC (programmable logic control- ler) can query the potential-free contact directly by wire, or this contact is integrated by interface modules, with, for example, the compact mes- sage system TC Mobile I/O X200. This means that the status of the protective devices in large

systems can be monitored not only in the control room, but also sent via SMS to the cell phone of the service technician. If a contactor is overloaded, trouble-free replacement is possible, in particular with the pluggable protective devices.

Figure 3: Integrated status indicator: Thanks to the surge protection components of Termitrab complete, the user is kept up-to-date regarding the state of their system at all times. Permanent installation with push-in technology Classical screw connection technology is still com- monly used. If there are many signal lines to be installed however, considerable time can be saved with the quick push-in connection technology (see Figure 4 ). Comparisons with screw connection technology have shown, for example, that the wires can be connected up to 50% quicker. Dis- connection is also easily possible by pressing the ‘pusher’. Depending on his preference, the install- er can choose between screw and push-in con- nection technology with the Termitrab complete product range.

In water and wastewater treatment, there is an increased failure risk in large systems due to surge voltages – with far-reaching consequences.

Figure 4: Convenient connection: Conductors can be connected quickly with push-in technology and removed without any special tools.

Electricity + Control

AUGUST 2017

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