Emerson E300 Series Design Manual page 354

Safety Product Mechanical
information information installation
output, such that when the speed is below a certain level, the elevator controller can open the doors early.
In RFC-A and RFC-S the speed threshold is based on speed feedback, but in Open loop mode it is based upon the profile generator speed since
there is no feedback device available.
J49 Velocity Threshold 2 Status Output
Mode Open-Loop, RFC-A, RFC-S
Minimum 0
Default
Type 1 Bit Volatile
Display Format Standard
Coding RO, ND, NC, PT
When set to On (1), this indicates when the elevator speed in mm/s, Actual Speed (J40) is <= Velocity Threshold 2 (H14).
When set to Off (0), this indicates when the elevator speed in mm/s, Actual Speed (J40) is > Velocity Threshold 2 (H14).
This threshold may be used for advanced door opening where Velocity Threshold 2 Status Output (J49) is routed to the lift controller via a digital
output, such that when the speed is below a certain level, the elevator controller can open the doors early.
In RFC-A and RFC-S the speed threshold is based on speed feedback, but in Open loop mode it is based upon the profile generator speed since
there is no feedback device available.
J50 Final Speed Reference
Mode RFC-A, RFC-S
Minimum −VM_SPEED
Default
Type 32 Bit Volatile
Display Format Standard
Coding RO, FI, VM, ND, NC, PT
Final Speed Reference (J50) shows the reference at the input to the speed controller.
J51 Drive Encoder Speed Feedback
Mode RFC-A, RFC-S
Minimum −VM_SPEED
Default
Type 32 Bit Volatile
Display Format Standard
Coding RO, FI, VM, ND, NC, PT
The speed feedback is taken from the drive position feedback interfaces or from a position feedback interface. It is also possible to select sensorless
speed feedback with Sensorless Feedback Mode (C14). Drive Encoder Speed Feedback (J51) shows the level of the speed feedback selected for
the speed controller.
The FI attribute is set for this parameter, so display filtering is active when this parameter is viewed with one of the drive keypads. The value held in
the drive parameter (accessible via comms or an option module) does not include this filter, but is a value that is obtained over a sliding 16ms period
to limit the ripple. The speed feedback includes quantisation ripple given by the following equation in rpm:
Ripple in Drive Encoder Speed Feedback (J51) = 60 / 16 ms / Position resolution
The ripple for a linear system is given by the following equation in mm/s:
Ripple in Drive Encoder Speed Feedback (J51) = Pole pitch in mm / 16 ms / Position resolution
The position resolution for each type of feedback device is defined in the table below.
Position feedback device
AB, AB Servo
FD, FR, FD Servo, FR Servo
SC, SC Hiperface, SC EnDat, SC SSI, SC Servo
EnDat, SSI, BiSS
For example the ripple in Drive Encoder Speed Feedback (J51) when a 4096 line AB type encoder is used is 0.23 rpm. It should be noted that no
filtering is applied to the speed feedback used by the speed controller or for the position feedback reference system unless the feedback
filter for that particular interface is activated by putting a non-zero value in the appropriate set up parameter (i.e. Drive Encoder Feedback
Filter (C09) for the Drive position feedback interface). The diagram below shows the filtering applied to the speed feedback when this is taken
from the Drive position feedback interface.
354
Electrical Getting
User Menu A Commissioning
installation started
4 x lines per revolution or pole pitch
2 x lines per revolution or pole pitch
1024 x sine waves per revolution or pole pitch
Comms bits per revolution or pole pitch
Advanced
Diagnostics Optimization CT MODBUS RTU Technical Data
Parameters
Maximum
Units
Update Rate
Decimal Places
Maximum
Units
Update Rate
Decimal Places
Maximum
Units
Update Rate
Decimal Places
Position resolution
1
Background
0
VM_SPEED
4 ms write
1
VM_SPEED
4 ms write
1
E300 Design Guide
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