Magnetek DSD 412, Техническое руководство

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DRIVE SETUP
78
One of two methods may be selected to Run
the drive and determine the direction. Use
function #115 to select.
1.) Hardware Run & Reverse (#115 = Off)
The Hardware Run input starts the drive.
The Reverse contact controls the direction.
The Drive & Field Enable signal must also
be energized and remain so for this to occur.
The desired direction command should be
stable before a non-zero speed reference is
selected. CAUTION – The direction control
from this input is not interlocked with any
other logic condition. This facilitates
direction control while re-leveling or
performing a quick reverse while heading for
a ‘home landing’, but it also means that an
intermittent contact or broken wire can make
the car go in the wrong direction!
2.) Run-Up & Run-Down (#115 = On)
Two separate logic inputs are provided to
start the drive in either the up or down
direction. The Drive & Field Enable signal
must also be energized and remain so for
this to occur. If both Up and Down
directions are active simultaneously, the
drive will not start. This prevents a single
relay contact or wiring failure from starting
the drive in the wrong direction. Once
running, the direction may be reversed by
closing the contact for the new direction and
releasing that for the old. This is allowed at
any speed. If the command contact
closures overlap, speed control will remain
active and the contactor will not drop.
Using Pre-Torque
When enabled by function #114, the value
and direction of the analog pre-torque signal
input will be captured and latched each time
the drive is started by closure of the motor
dc loop contactor in response to activating
the Run command. That value will be used
to pre-load the speed error integrator and
provide a starting value of motor armature
current and torque. When set properly, that
torque will be sufficient to hold the elevator
car and prevent rollback. Operation is fully
automatic when enabled by function #114.
No external sequencing is necessary. If
serial link control is ON, the pre-torque value
will be from the serial link.
Using External Velocity Commands
Operation with an external analog velocity
command is similar to the sequences above.
This mode is programmed via the logic
select function #110. Setting #110 to a 1
enables the bi-directional analog follower
mode. The actual car direction will always
follow the polarity of analog reference. Both
the Drive & Field Enable and the Hardware
Run signals must be active to cause the
drive to run. When function #110 is set to 4,
the uni-polar analog follower mode is active.
The drive will control the speed of the
elevator based on the positive value of the
supplied analog reference. The direction of
travel will be determined by the status of
either the direction select (function #115
=OFF) or Run-Up/Run-Down (function
#115=ON) logic input command lines. Both
the Drive & Field Enable and the Hardware
Run signals must be active to cause the
drive to run.
Analog reference wiring is sensitive to
electrical noise interference. The reference
signal channels are differential and should
be wired with twisted pair, shielded cable, as
shown in Figure 7: Typical Analog Signal
Wiring. Be sure that the cable shield is
connected only at the drive end.