UT_MOTOR_2SPD — Two-speed starter (Dahlander or separate windings)

Low and high speed contactors that are never on together, plus an optional
star-bridge contactor for Dahlander motors, with a changeover dead time and an
optional "start in low first". Modes, interlocks, protection, faults and restart
rules are as UT_MOTOR.

Pins

Always wire the contactors' NC auxiliaries as a hardware interlock as well. The
block never turns both on, but only the wiring stops a welded contactor.

Record UT_MOTOR_2SPD_DATA (pin Spd)

A negative speedChangeDelay or lowStartTime acts as 0 and raises a config warning
(wrnConfig). Everything else (modes, protections, cmdStart / cmdStop, status) is
in the motor record Data.

How it works

• Speed. Auto: AutoHigh. Hand: cmdLow / cmdHigh choose the speed and start
  it; cmdStart and LocalStart start at the speed chosen last. Low and high
  together do nothing. The speed commands are ignored (and cleared) in Off and Auto.
  Switching Auto → Hand keeps the speed it was running at.
• Start in low: with startInLow, a run asked for high starts in low, stays there
  lowStartTime, then changes up through the dead time. Once a run has done that (or
  has been at high), later changes up go straight to high after the dead time.
  Without startInLow, high starts directly.
• Changing speed while running: the running contactor goes off at once, the dead
  time runs, then the other contactor comes on. The motor stays requested the whole
  time, so Running stays on, a permissive does not stop it, and the restart delay
  does not apply. If the request goes back to the old speed during the dead time, that
  contactor comes straight back on.
• Starting after a stop: the same speed starts at once; the other speed waits
  until speedChangeDelay has passed since the last contactor went off.
• After a power-up either speed waits speedChangeDelay first, because the motor
  may still be turning.
• With feedback supervised (useFeedback, not in simulate), the new speed also
  waits until the other contactor's aux shows open; with speedChangeDelay = T#0s
  there is still at least one scan with both off.
• Changeover protection (changeover, bit 9, TRIP · MANUAL by default) trips when
  both auxes show closed, when the aux of the speed that is off shows closed while the
  other speed is on, or when a contactor switched off for a speed change still shows
  closed after stuck.delay (the other speed is never switched on into it). A contact
  that stays closed at standstill is the welded-contactor protection (stuck).
• If the new speed's aux does not confirm after a change, feedbackLost trips; if the
  motor never had feedback, noFeedback does.

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_SPEED_CHANGE (speed change delay) · UT_F_LOW_START_TIME (low start time), both when negative, and uses UT_F_CHANGEOVER for its changeover protection.
The rows marked (this block) come from its own sequence and show from the scan after it changes.

Using it

Fan1(AutoCmd := Vent.Run, AutoHigh := Vent.Boost, FeedbackLow := K1_Aux, FeedbackHigh := K2_Aux,
     Overload := Fan1_OL, Data := Fan1Data, Spd := Fan1Spd);
K1 := Fan1.RunLow;
K2 := Fan1.RunHigh;
K3 := Fan1.Bridge;