System Calibration - Renishaw TONiC FS T3 Series Functional Safety Installation Manual And 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.
NOTES: 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 RTLC20-S 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.
NOTE: Only the chosen reference mark that has been used in the calibration routine is guaranteed to
remain phased.
X The system automatically exits the CAL routine and is ready for operation.
X For the safety function to be valid, customer commissioning tests must be performed:
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 'RTLC20-S scale 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.
X For the safety function to be valid, customer commissioning tests must be performed:
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
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.
7), and re-calibrate the system.
13, and re-calibrate the system.
14