System Calibration - Renishaw TONiC FS T301 Series Functional Safety Manual

System calibration

Calibration is an essential operation that completes readhead set-up, with the optimum incremental
and reference mark signal settings stored in the readhead's non-volatile memory.
Before system calibration
X Clean the scale and readhead optical window (contamination around the reference mark may result in
reference mark dephasing).
X If re-installing the readhead, restore factory defaults.
X Maximise the signal strength along full axis of travel.
NOTE: Calibration (CAL) routine should be carried out at slow speed (<100 mm/s or less than the
readhead maximum speed, whichever is slowest).
Step 1 – Incremental signal calibration
X Ensure Automatic Gain Control (AGC) is switched off – Calibration (CAL) LED on readhead is not
illuminated – before beginning calibration.
X Press and release the CAL button on the end of the interface using a 2 mm Allen key or similar tool as
shown.
NOTE: Activating the CAL switch only requires 2.5 N force. Applying excess force may permanently
damage the switch.
Ti interface
X The CAL LED will now periodically single-flash to indicate that it is in incremental signal calibration
mode.
X Move the readhead along the axis, ensuring you do not pass the selected reference mark, until the CAL
LED starts double-flashing, indicating the incremental signal is now calibrated and the new settings are
stored in the readhead memory.
X The system is now ready for reference mark phasing.
X For systems without reference mark, go to 'Calibration routine – manual exit'.
X If the system does not automatically enter the reference mark phasing stage (no double-flashing
of the CAL LED) the calibration of the incremental signals has failed. After ensuring failure is not due
to overspeed (>100 mm/s or exceeding the readhead maximum speed), exit the calibration routine,
restore factory defaults and check the readhead installation and system cleanliness before repeating the
calibration routine.
TONiC RSLM20/RELM20 Functional Safety installation guide and safety manual
Set-up LED
CAL button
DOP interface
Original instructions
Step 2 – Reference mark phasing
X Move the readhead back and forth over the selected reference mark until the CAL LED stops flashing
and remains off. The reference mark is now phased.
X The system automatically exits the CAL routine and is ready for operation.
For the safety function to be valid, customer commissioning tests must be performed:
X
see 'Commissioning test' on page 3.
X If the CAL LED continues double-flashing after passing the chosen reference mark many times, it is not
detecting the reference mark.
- Ensure that the correct readhead configuration is being used. Readheads can either output all
reference marks or only output a reference mark where a reference selector magnet is fitted.
- Check that the reference selector magnet is fitted in the correct location relative to readhead
orientation (see 'TONiC FS T301x readhead installation drawing' on page
NOTE: The LED on the interface will flash blank when the reference mark is detected (>100 mm/s only).
It indicates the presence of a reference mark, not the phasing status.
Calibration routine – manual exit
X To exit the calibration routine at any stage press the CAL button. The CAL LED on the readhead will then
stop flashing.
For the safety function to be valid, customer commissioning tests must be performed:
X
see 'Commissioning test' on page 3.
CAL LED Settings stored
Single-flashing None, restore factory defaults and re-calibrate
Double-flashing
Incremental only
Off (auto-complete) Incremental and reference mark
Restoring factory defaults
When re-installing the system, or in the case of continued calibration failure, factory defaults should be
restored.
To restore factory defaults
X Switch system off.
X Press and hold the CAL button whilst switching the system on. The CAL LED on the readhead will flash
several times, indicating that the factory defaults have been restored.
X Release CAL button.
X Check 'Readhead mounting and alignment' on page 14
NOTE: System must be re-calibrated after restoring factory defaults.
Switching AGC on or off
AGC can be switched on or off via the interface.
X Press and hold the CAL button on the interface for >3 seconds to switch AGC on or off.
The CAL LED on the readhead will be illuminated when AGC is active.
NOTE: The system must be calibrated before switching AGC on.
6).
and re-calibrate the system.
15