NS OM-6x
4.4.1 Model NS OM 61
The contacts actuated by the float are attached to a perfor-
ated rail inside the contact tube. They are factory installed
based on the order data and can later be moved higher or
lower (note minimum spacing!). Proceed as follows:
• Disconnect the voltage supply.
• Disconnect connectors or open plug housing and undo
connections!
• Unscrew the plug base.
• Carefully pull the perforated rail with contacts out the
top.
NOTICE
On versions with earth wire, this is run as a loop and soldered
to the protective tube from the inside in the insertion direc-
tion. To prevent breaking off the earth wire it should not be
pulled all the way out.
We recommend marking the original contact position for
checking purposes. The contacts can then be locked into place
in the desired position on the perforated rail. The contacts are
installed as NO, NC or changeover based on the order. Since
these are bistable contacts, the contact function of the NO or
NC contact can later be changed. To do so, simply turn the
contacts 180°.
The contact symbols for NO and NC are marked on the hous-
ing. Below the respective symbol you will also see an arrow.
The arrow, which points up when installed, indicates the re-
spective contact function (see drawing).
Function NO contact (NO)
with rising level
The contact logic assumes the level switch is installed in an
empty tank, i.e. it is only in the operating position once filled.
After positioning the contacts, slide the perforated rail back
into the protective tube. Please route the additional cable
lengths required to move the contacts as a loop and insert
along with the perforated rail.
If the loop for the earth lead was removed from the protective
tube, first insert this lead again, then slide in the perforated
rail.
Screw on the plug base or the plug housing.
10
Bühler Technologies GmbH
Function NC contact (NC)
with rising level
BX100010 ◦ 03/2021