HBK U9C, Mounting Instructions

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U9C
CONDITIONS ON SITE
12
6 CONDITIONS ON SITE
U9C series force transducers are made of rustless materials. It is nevertheless important
to protect the transducers from weather conditions such as rain, snow, ice and salt water.
6.1 Ambient temperature
The effects of temperature on the zero signal and on sensitivity are compensated
.
To obtain optimum measurement results, comply with the nominal (rated) temperature
range. The compensation of the temperature effect on the zero point is implemented with
great care, but temperature gradients can still have a negative effect on the stability of
zero. Constant or very slowly changing temperatures are therefore best. A radiation
shield and all-round thermal insulation produce noticeable improvements. However, they
must not be allowed to set up a force shunt, i.e. slight movement of the force transducer
must not be prevented.
6.2 Moisture and corrosion protection
The force transducers are hermetically encapsulated and are therefore very insensitive to
moisture. The transducers achieve protection class IP67
.
Despite the careful encapsulation, it makes sense to protect the transducers against per­
manent exposure to moisture.
The force transducer must be protected against chemicals that could attack the steel.
With stainless steel force transducers, note that acids and all materials which release
ions will in general also attack stainless steels and their welded seams. Should there be
any corrosion, this could cause the force transducer to fail. In this case, appropriate pro­
tective measures must be provided.
The housing of the inline amplifiers is made of aluminum and, like the sensor, meets the
requirements of IP67 protection. We recommend protecting the amplifier housing from
sustained weather effects.
6.3 Deposits
Dust, dirt and other foreign matter must not be allowed to accumulate sufficiently to di­
vert some of the measuring force around the force transducer, thus invalidating the mea­
sured value. (Force shunt). Also remember to lay the connection cable so that no force
shunts are produced at the lower nominal (rated) forces (<1 kN).