Applications with spark safety requirements
Some applications require so-called spark safety to be guaranteed. This means that even in the event of a fault, there must be no electrical flashover (i.e., spark), which could cause, for example, unwanted ignition of the explosive atmosphere. We usually encounter similar applications in a mine surrounding (hazardous concentrations of methane or coal dust), possibly in the chemical industry.
For these reasons, not only in the mentioned operations, isolated systems are used, which can be monitored by means of insulation monitoring devices, and thus respond to possible electric power line insulation faults. Insulation monitoring devices in these areas usually measure the insulation resistance before the network is switched on and during its operation, and ensure immediate disconnection of the system power supply in case of response to an insulation fault. This is done by means of the device’s relay output and the fuse element controlled by it.
However, the insulation monitoring device is an active device, and even after the main system is disconnected from the power supply, its measuring functions do not stop. Therefore, it is necessary to ensure that the measuring circuit of the insulation monitoring device itself is so-called non-flammable - it can be operated in intrinsically safe operation.
HAKEL company offers HIG97 device for these purposes. This device has a non-flammable measuring circuit (examination was performed by the accredited laboratory FTZÚ Radvanice) and extremely fast response to insulation fault (device detects an insulation fault within a maximum of 80 ms from its occurrence). This ensures that this insulation monitoring device is suitable for a similar surrounding. Device is intended to monitor AC systems and in combination with TL1200 inductor enables to monitor IT power supply systems up to 1200 V AC operating voltage.
APPLICATIONS WITH SPARK SAFETY REQUIREMENTSNahrávám ...By ticking this box you will give us the information that you are not sure about the correctness of your selection. However, it is necessary to send an inquiry.