
TONiC RKLC20-S linear installation guide
10
P limit magnet
Remove
self-adhesive
backing paper
Reference mark
selector magnet
Selected IN-TRAC
reference mark
Q limit magnet
Magnet applicator tool
NOTES:
u
Reference and limit magnets may creep when influenced by magnetic materials in
close proximity. In such cases, they should be held in place using an additional fillet of
epoxy glue or similar along the outer edge of the magnet assembly.
Optional bolted reference and limit magnets are available
('RKLC20-S scale installation drawing', page 5)
.
u
The reference mark selector and limit actuator locations are correct for the readhead
orientation shown.
u
The reference mark selector magnet is only required for ‘Customer selectable reference
mark’ readheads. For more information refer to
TONiC
™
encoder system
Data sheet
(Renishaw part no. L-9517-9337).
u
External magnetic fields greater than 6 mT, in the vicinity of the readhead, may cause
false activation of the limit and reference sensors.
Limit trigger point
The limit output is nominally asserted when the readhead limit switch sensor
passes the limit magnet leading edge, but can trigger up to 3 mm before that edge
('RKLC20-S scale installation drawing', page 5)
.
Reference mark selector and limit magnet installation
IMPORTANT:
Allow 24 hours after scale application before fitting magnets.
For accuracy and ease of positioning of reference mark selector and limit magnets, the
applicator tool should be used. The magnet should be attached to the applicator tool as
shown. Limit magnets can be positioned at any user defined location along the scale,
but the reference mark selector magnet should be positioned adjacent to the selected
IN-TRAC
reference mark as shown.
As the TONiC readhead passes the reference mark selector magnet or limit switch
magnet, a force of up to 0.2 N is generated between the magnet and the concentrators
on the readhead. The design of the bracket should be sufficiently stiff so that it is able to
tolerate such force without distorting.
Following the clamping instructions on the scale installation will prevent this magnetic
force from disturbing the scale.