Magnetek DSD 412, Техническое руководство

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DRIVE SETUP
80
Serial Communication Specification
See Function #110 to enable this feature.
The serial communication link between a
host and the DSD 412 consists of two
messages. There will be a
Demand
Velocity/PreTorque Command sent from the
host to the DSD 412 every 15 MS. There will
be a
Demand Velocity Response message
sent from the DSD 412 to the host every 45
MS.
After power up the drive will wait 10 seconds
for the first Drive Velocity Command (DC)
message
to be received from the car controller. If this
time expires, a 20 SEC COMM FLT (F117)
will be declared. Once communications has
been established, a valid DC message must
be received at least in 150 MS intervals. If
this time window expires, a 150 MS COMM
FLT (F118) will be declared.
Frame format: 10 bits (N81) @ 19.2K baud.
RS232 may be used with the 46S02975-
03xx Drive Control PCB at connector J2.
RS422 requires the 46S02975-04xx PCB
with a DB9 J1 connector. Pin-out is per
Figure 21: Serial Link Connections
Demand Velocity Command message from the host is as follows:
Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7 Byte 8
Sync
Byte
FAh Sync
Byte
05h Logic
command
Byte 1 Logic
comman
d Byte 2 Numeric
command
(high byte) Numeric
command
(low byte) PCDU
keystroke Checksum
Bytes 1&2:
These bytes will always be set to FAh and 05h respectively. They are used for
the purpose of synchronizing the DSD 412 to the start of an incoming message from the host.
Byte 3:
{N259_C001} This byte contains the logic commands sent from the host to the DSD 412.
The bit definitions are listed below:
B0:
=1 to act as a synchronization bit for incoming messages from the host.
B1: =1 to act as a synchronization bit for incoming messages from the host.
B2: 0=Stop requested 1=Run requested
B3: 0=No request to clear faults 1=Clear fault requested
B4: 0= Demand Velocity is not DOWN 1= Demand Velocity is DOWN
B5: 0= Demand Velocity is not UP 1= Demand Velocity is UP
B6: 0=Idle field command 1=Full field command
B7: A rising edge of this signal acts as a latch to capture the Numeric Command and interpret
it as a new Pre-Torque value. This signal should be set to a zero by the host before it sends a
new Pre-torque value or when the host receives confirmation that the drive is in the run mode.
Byte 4:
{N259_C002} This byte contains additional logic commands from the host to the DSD
412. [Drive function #104 must be set to a 1 for this control to be active.]
B0:
0= No gain reduction 1= Velocity loop gain reduction is ON
B1-B7 are spares
Bytes 5&6:
{N259_C000} These two bytes represent a signed 16 bit numeric value. The
definition of this value is determined by the status of Byte 3, Bit 7. If bit 7 is a 1, the value will be
interpreted as a pre-torque signal. If byte 3, bit 7 is a 0, the value will be interpreted as a velocity
reference.. The limits for this value are: 7FFFh = +1 per-unit, 0000h = zero, 8000h = -1.0 per-
unit.
Byte 7:
The data in this byte is passed to the PCDU routines and is interpreted as a new PCDU
keystroke. If no 'key' is being pressed (a great majority of the time) the value of this byte will be
00h. It is the responsibility of the host to insure that this byte contains the new non-zero
keystroke data for only one 15 MS transmission period. If this is not done, the DSD 412 will act
as if a given key is being 'held down' instead of being pressed and released. The host must pace
the placement of non-zero data in this byte no more frequently than one character every 250 MS.