UT_MOTOR_VSD — Variable speed drive

Runs a VSD/VFD over hard-wired I/O (run, running, ready and fault relays, speed
reference and feedback). It adds speed limits, ramps, a skip band, a hand speed,
speed-deviation supervision and a drive-reset pulse. Modes, interlocks and the
common protections are as UT_MOTOR (it is
UT_MOTOR_CORE and a speed reference).

Pins

Record UT_MOTOR_VSD_DATA (pin Vsd)

The deviation limit and time are the speedDev protection's own sp and delay.

Also used in the motor record Data

Protections (bits as UT_MOTOR)

drive is in Data; speedDev and driveNotReady are in Vsd:

The overload is inside the drive, so there's no Overload pin. The other
protections are UT_MOTOR's.

How it works

• The reference. Hand → handSpeed, Auto → AutoSpeed, or grpSpeed while a
  group (UT_PUMP_CASCADE) owns the record (grpActive, set by the
  group every scan); a drive no group owns never looks at grpSpeed. Clamped to
  minSpeed..maxSpeed, then kept out of the skip band, then ramped. A start begins
  from minSpeed; when the drive is stopped (Off, interlock, fault…) the reference is 0.
  A request that is not a number (NaN, infinity) keeps the last good one.
• Skip band. The reference is never inside skipLow..skipHigh (the edges
  themselves are allowed). A request inside the band holds at the edge on the side
  the reference is coming from; a ramp crossing the band jumps over it. If
  minSpeed is inside the band, the drive starts at skipHigh.
• Ramps use real elapsed time, so they take the same time at any scan rate.
  A lowered maxSpeed takes effect at once. The rate is in % of full speed per
  second, or per minute with rateUnit := UT_PER_MIN: accelRate := 10.0 is
  0 → 100 % in 10 s per second, or in 10 min per minute. To copy a drive's
  "0 to full speed in 20 s" ramp, use 5 %/s (accelRate := 5.0) or
  300 %/min (accelRate := 300.0, rateUnit := UT_PER_MIN).
• SpeedRefRaw = rawMin + SpeedRef / 100 × (rawMax − rawMin), rounded, held to 0..65535.
• DriveReady FALSE blocks a start (Ready is FALSE). Lost while running, it
  raises driveNotReady, which by default warns and keeps the drive running; set
  it to TRIP to stop the drive.
• In simulation (simulate) the drive fault and driveNotReady still act; the
  speed feedback is taken as the reference, so speedDev does not act.
• DriveReset pulses for resetPulse when a fault is reset (pin, cmdReset,
  or switching to Off), and also when a reset is asked for while DriveFault is
  still on: most drives hold their fault relay until they get the pulse. One reset
  request gives one pulse: a cmdReset held TRUE (or a Reset pin held on) gives
  one pulse and resets once.
• AtSpeed: with SpeedFb wired, running and within speedDev.sp of the
  reference; without it, running and the ramp has reached its target.

Wiring the drive's relays

Invalid settings

A setting that would run the drive unsafely keeps it off with a fault: Fault,
wrnConfig and faultCode bit 12 "Invalid setting". That is minSpeed above
maxSpeed, minSpeed above 100, maxSpeed below 0, either one not a number, and
rawMin / rawMax not numbers, outside 0..65535 or equal. Fix the setting and the
drive is back in service (in Auto at once; in Hand press start again).

Other invalid settings fall back and warn (Warning, wrnConfig, bit 12), and
the drive runs: minSpeed below 0 (0 is used), maxSpeed above 100 (100),
accelRate / decelRate negative or not a number, or an unknown rateUnit (no
ramp here: the drive's own ramp), a skip band not a number or with skipLow above skipHigh (off),
handSpeed not a number (the last good request), a negative resetPulse (one
scan), ratedHz / ratedRpm negative, NaN or infinite (speedHz / speedRpm 0). The common settings are checked as in UT_MOTOR.

Status

statusCode, faultId and statusText say the one main thing the motor is
doing, or what holds it back, so a technician can see on the HMI why it is not
running without opening the program. A motor asked to run that is not running
always shows a held, fault or configuration status. The most important reason wins:
configuration > fault > held / waiting > warning > running > idle. A warning shows
over "Running" so it is seen. The time that goes with a status is in timeLeft.
The text is rebuilt only when the status or the fault changes. The numbers are in
conventions.

<fault> is faultId, one of: UT_F_OVERLOAD (overload) · UT_F_MOTOR_HOT (motor
too hot) · UT_F_NO_FEEDBACK (no run feedback) · UT_F_FEEDBACK_LOST (feedback
lost) · UT_F_WELDED (contactor welded) · UT_F_CURRENT_HIGH (current high) ·
UT_F_CURRENT_LOW (current low) · UT_F_DRIVE (drive fault) · UT_F_SPEED_DEV
(speed deviation) · UT_F_CHANGEOVER (changeover) · UT_F_DRIVE_NOT_READY (drive
not ready).
<setting> is one of: UT_F_FLC (full load current) · UT_F_CURRENT_NEEDS_FLC
(current needs FLC) · UT_F_START_MASK (start mask) · UT_F_RESTART_DELAY (restart
delay) · UT_F_HAND_MAX_RUN (hand max run) · a protection's name (its delay,
recover or maxRetries).
This block adds the settings UT_F_MIN_MAX_SPEED (min / max speed) · UT_F_RAW_MIN_MAX (raw min / max) (UT_ST_CONFIG when they keep it off) · UT_F_ACCEL_RATE (accel / decel rate) · UT_F_SKIP_BAND (skip band) · UT_F_HAND_SPEED (hand speed) · UT_F_RESET_PULSE (reset pulse) · UT_F_RATE_UNIT (rate unit) · UT_F_RATED_HZ_RPM (rated Hz / rpm), and uses UT_F_SPEED_DEV and UT_F_DRIVE_NOT_READY for its own protections.
The rows marked (this block) come from its own sequence and show from the scan after it changes.

Using it

P1(AutoCmd := Station.Run1, AutoSpeed := PressurePID.XOUT, Feedback := P1_Running,
   DriveReady := P1_Ready, DriveFault := P1_Fault, SpeedFb := P1_SpeedPct, Data := Pump1Drive,
   Vsd := Pump1Vsd);
P1_RunRelay := P1.Run;
P1_SpeedAO := P1.SpeedRefRaw;
P1_ResetRelay := P1.DriveReset;