From RTE 34.16.01.

Compensation is done by adding the selected compensation value (specified in a table of points) to the ideal positions.

For the compensation depending on position, linear interpolation is applied.

Input values for direct compensation are IP_F, output values are IP_C.

The input values for inverse compensation are the CP, the output values are the CP_C.

Obviously, the offsets are applicable after the axes involved have already executed the homing cycle (C0_DONE).

The function is enabled via bit 12 of the predefined variable SYS_CFG.

Enabling its use results in:

•The MVA_OPEN_LOOP function (also used by RPE in missing power) will impose: IP(ax) = CP_C(ax).

•The EPOS position error will be calculated using the P_IP_C (ip_c of n previous rules)

•IP_C is used as the reference position for Fieldbus devices (CAN, ECAT).

To complete, two functions have been implemented so that compensation tables can be used at will:

•result = PLANAR_COMP_IP (STRU_AAX posIn, STRU_AAX poOut), applies direct compensation

•result = PLANAR_COMP_CP (STRU_AAX posIn, STRU_AAX poOut), apply reverse offsets

Compensation tables can define:

•Planar reference two axes (called for convenience x and y) with compensation enabled on x and y

•Planar reference two axes (called for convenience x and y) with compensation enabled on x, y and z (third axis undergoing compensation depending on position in the plane)

•Planar two-axis reference (called for convenience x and y) with compensation enabled only on a third z-axis (third axis undergoing compensation depending on position in the plane).

•Linear reference of one axis (called x for convenience) with compensation enabled on x

•Linear reference of one axis (called x for convenience) with compensation enabled on z (second axis undergoing compensation depending on x-axis position)

If several tables compensate the same axis, the resultant compensation will be the sum of the compensation of the various tables.

It must be kept in mind that the input positions for calculating the compensation use those compensated up to that point.

That is, having two tables used to compensate the same axis, the first one (in order of definition) is compensated using the IP_F, the second one starts to compensate using the IP_C generated by the first table.

(Example of use: linearization of Z as a function of the x, y plane and then correction of Z-axis deviations)

NOTE: The order of execution corresponds to the order in which the tables are defined in the configuration files.

NOTE: Compensation tables are assumed only at switch on.

NOTE: Configuration of compensation tables is done either in RTE.CFG file (phase 0) or in "/FA/PCTDEF.CFG" file.

Diagnostics

While reading configuration from file "/FA/PCTDEF.CFG" in case of RTE error:

•Generates the extended diagnostic in the report

•Imposes bit 10 in the BAD_CONFIG parameter.

•Generates the alarm: 9211 PCTDEF.CFG config. fault(code:%d line:%d)