Answer / r k nair

Normal Cable Gland is also called Single Compression Cable
Gland. As the name suggests, while you tighten the gland,
the grip or compression is effected only at one p[lace
(i.e.) at the cable armour only. There is scope for
moisture and corrosive vapour to enter the gland and thus
into the cable.

Whereas in Double-Compression Glnad, the compression
happens both at the cable armour as well as at the inner
sheath. This is sort of two sealings. Hence, chances of
moisture or vapour entry are minimised. Hence these glands
are also known as Weather-proof cable glands or Flame-proof
cable glands.

Answer / raffi

Single compression glands used for the unarmoured
cables.since you can make the grip only on cable sheath
whereas Double compression glands are used for armoured
cables as we can tight it with both cable inner sheath also
in cable armour.

Both glands can be used for exlosion proof areas, only
thing is that it should be certified for zone
classifications

Answer / sumith

single compression cable gland is used for normal panels and
it is not airtight.(it cant be used in flammable areas)
double compression cable gland is used for air tight panel i.e
purge panels(used in flammable areas)

We do have a problem in the company that is one PT connected to PlC which is mean 1 out of 1 in PLC system we do have the PAHH is 55 mbar and PALL 8 mbar with a timer of 15 sec for the PAHH the problem started when PAHH goes more than the set point which is 55 it reached up to 71 but due to timer doesn't trip . We force it and we checked everything nothing there . We replaced the transmitter problem still there the reading goes more than the 55 bar the range for transmitte is 0- 60 mbar . So we did loop check , aculaizing valve , wiring all are okay . What the possible causes for this ???

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