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SM-Uni Enc Pl

Parameter

structure

Keypad and

display

Parameter

x.00

Parameter

description format

Advanced parameter

descriptions

Macros

Serial comms

protocol

Electronic

nameplate

Performance RFC mode

270

Unidrive SP Advanced User Guide

www.controltechniques.com Issue Number: 10

In SINCOS mode (6) ONLY with no comms or commutation inputs, the internal differential Cos signal is written to this parameter as an unsigned
number.
A value greater then 32768 in Pr

x.42

requires the user to minus 65536 to get the negative result.

In AB.SErvo (3), FD.SErvo (4) or FR.SErvo (5) mode, Pr

x.43

equals zero.

All other modes follow the description for Pr

x.44

This parameter has no effect for SC.SErvo encoders.

If Pr

x.44

is zero the drive can check the position derived with the sine and cosine waveforms from a SinCos encoder via serial communications.

If Pr

x.44

is set to one the checking is disabled and encoder comms is available via the transmit and receive registers. The transmission system can

be used to communicate with encoders provided the mode is either SC.HiPEr or SC.EndAt.

For further detailed information refer to the

SM-Universal Encoder Plus User Guide

At power-up Pr

x.45

is initially zero, but is set to one when the encoder connected to position module has been initialized. The drive cannot be

enabled until this parameter is one.
If the encoder power-supply is lost, or the encoder type parameter is changed for an encoder connected to a Solutions Module, and the encoder type
is SC, SC.HiPEr, SC.EndAt or EndAt the encoder will no longer be initialized. When an encoder is no longer initialized Pr

x.45

is reset to zero and the

drive cannot be enabled. The encoder may be re-initialized, provided the drive is not active, by setting Pr

3.47

to one. Pr

x.45

is automatically reset to

zero when the initialization is complete.

The LPR divider Pr

x.46

is used to scale the equivalent lines per revolution in Pr

x.10

of incremental and SinCos encoders, without comms, on rotary

motors, and all but comms only encoders on linear motors. (Servo encoders must have the same number and pitch of poles as the motor).
The equivalent line per revolution parameter (Pr

x.10

) is divided by the value in Pr

x.46

. This can be used when an encoder is used with a linear

motor where the number of counts or sine waves per pole is not an integer.

Example

128.123 lines per revolution would be set as 128123 in Pr

x.10

and 1000 in Pr

x.46

giving:

128123 / 1000 = 128.123. If the value is less than 1, the value used will be 1.
When using SinCos encoders with comms, the comms and SinCos positions must be aligned. The comms position resolution may be a multiple of the
analog position resolution. When a linear encoder type has been selected (Pr

x.16

= 0) the value in Pr

x.09

is this multiple.

The motor pole pitch used to configure EndAt and Hiperface encoders is that of the currently selected motor map.

When setting larger values in Pr

x.10

when the Solutions Module is the main feedback device, the drive will limit the maximum speed, which in turn

limits the maximum of some of the drive parameters such as Pr

1.06

and Pr

1.21

. If the overall value of the LPR after division is low once more, the

parameters that have been limited will not return to their original values and may need to be increased. An ELPR of 10,000 gives a maximum speed
of 3000rpm.

When operating with an Incremental plus commutation (absolute encoder), Ab.SErvo, Fd.SErvo, Fr.SErvo or SC.SErvo this parameter should remain
at default (Pr

x.46

= 1).

x.43

Encoder comms receive register/Cos signal value

Uni

0 to 65535

Update rate: Background write

x.44

Disable encoder position check

Bit

OFF (0) or On (1)

OFF (0)