Decentral Solutions
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Safety functions in connection with installation
When a brake resistor is installed, the best
possible endeavours should be made to avoid
overloads, as the heat generating from a brake
resistor may involve a fire risk.
NOTE
The brake resistor should be fitted to a
nonflammable material.
For protection of the installation, a thermal relay
is fitted that cuts out the variable frequency drive
if the brake current is too high. Danfoss
’
40%
brake resistors contain a KLIXON switch. Flat
pack resistors are self-protecting.
The brake current setting on the thermal relay
is calculated as follows:
R
BR
is the brake resistor value at any given time.
The drawing shows an installation with a thermal relay.
MG.90.F2.22 - VLT is a registered Danfoss trademark
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