Commissioning
5.8 Commissioning the Encoder
Control Units CU240S
108
Operating Instructions, 07/2008 - FW 3.2, A5E00766042B AD
5.8.2
Encoder Fault Codes
Description
The Encoder Interface has only one fault code, – F0090. This condition occurs when the
allowed frequency rate of change, set in P0492[3] is exceeded or when low speed encoder
loss is detected.
Note
The reason for the encoder loss will be given in the level 3 parameter r0949:
r0949 = 1 - Encoder loss detected due to sudden speed change (i.e. speed change detected
on the encoder in a single scan > value in P0492).
r0949 = 2 - Encoder signal lost whilst running at low speed.
r0949 = 7 - Encoder loss detected due to motor stalled.
CAUTION
Optimum signal clarity is achieved when differential wiring is used between the encoder
and encoder module. This is especially useful when situated in a noisy environment or with
long cables – however, the module will function correctly both with single ended or
differential wiring and as such can tolerate a wire break when differential wiring is used. If
the module loses the complete signal on either A or B lines, the inverter will report F0090.
Remedial action on fault condition
Should the encoder give a fault message F0090 the following remedial action should be
performed:
1.
Check that an encoder is fitted. If the encoder is not fitted, set P0400 = 0 and select
SLVC mode (P1300 = 20 or 22).
2.
Check the connections between the encoder and the inverter.
3.
Check the encoder is not faulty (select P1300 = 0 and run at a fixed speed then check the
encoder feedback signal using r0061). Check for correct magnitude and direction of
speed.
4.
Increase the encoder loss threshold in P0492.
5.
Increase encoder low speed loss detection delay in P0494.
