Answer / v.govindarajulu

In Thermal Magnetic Release shortly known as TMD release
gives two types of Protection which are overload and short
circuit Protection, In termal Property ( ie metal gets
elongated when heating) is used to sense the overload (
over curent causes high heat in bimettalic strip). and
Magnetic Property (ie Magnectic Flux / induction) is used
to sense the short circuit.

note: short circuit protection needs quick trip than
overload trip thats why thermal trip is used for Overload
Protection And Magnetic Property is used for shortcircuit
Protection.


In Microprocessor release, sensing and triping executed by
Micrprocessor in gives the very faster response than TMD
Release. Normally Microprocessor based release gives LSI
Protection. ( G is Optional)

Answer / manojkrishnan

The thermal-magnetic release tripping circuit works with the
advantage of bimetallic strip, on which a heating element is
wound and so it needs particular time to trip ( heat up the
metallic strip > open circuit the holding coil > opens the
contacts ) .But the microprocessor based CB trips more
rapidly as we can set the tripping current,sensitivity and
tripping time more accurately with the help of a CT or a
current sensing resistor (in DC ).

Answer / naveen sahariya

fault sensing time is less in microprocessor release

Answer / mustafa

Thermal magnetic uses bimetallic strips- manual reset

Answer / naveen

in thermal magnetic release movement of the parts involved
where as in microprocessor based release is static device
no wear and tear

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