ABB HVC-02B 3HNA011999-001 Robot high voltage board
A relay module is provided with a multiple of
separate operation stages, each with its own
operation indicator shown on the display and a
common trip indicator on the lower part of the
front plate of the relay module.
The starting of a relay stage is indicated with one
number which changes to another number when
the stage operates. The indicator remains glow ing although the operation stage resets. The
In addition to the protection functions the relay
module is provided with a self-supervision sys tem which continuously supervises the function
of the microprocessor, its program execution
and the electronics.
Shortly after the self-supervision system detects
a permanent fault in the relay module, the red
IRF indicator on the front panel is lit . At the
same time the module puts forward a control
signal to the output relay of the self-supervision
system of the protection relay.
In most fault situations a fault code, indicating
the nature of the fault, appears on the display of

indicator is reset by means of the RESET push
button of the relay module. An unreset opera-
tion indicator does not affect the function of the
protection relay module.
In certain cases the function of the operation
indicators may deviate from the above princ-
ples. This is described in detail in the descrip-
tions of the separate modules.
the module. The fault code, which consists of a
red figure "1" and a three digit green code
number, cannotbe removed from the display by
resetting. When a fault occurs, the fault code
should be recorded and stated when service is
ordered. When in a fault mode, the normal
relay menus are operative, i.e. all setting values
and measured values can be accessed although
the relay operation is inhibited. The serial com-
munication is also operative making it possible
to access the relay information also from a
remotesite. The internal relay faultcode shown
on the display remains active until the internal
fault possibly disappears and can also be re-
motely read out as variableV 169.