VLT
®
Series 3500
77
★
= ROM default setting.
✔
= Normal Danfoss setup. Text in ( ) = display text. Figures in [ ] are used when communicating with the bus.
403 Terminal 19 (INPUT 19)
Value:
★
Reverse direction (REVERSING)
[0]
Start with reversing (START REV)
[1]
No operation (NO OPERATION)
[2]
External H-O-A Hand (EXT. HOA HAND)
[3]
Latch start hand (LATCH ST.HAND)
[4]
Function:
Using this parameter, terminal 19 can be used for changing
the direction of rotation of the motor, remotely switching to
“Hand” operation, or starting using “3-wire control”.
NOTE:
It is not necessary to stop the drive to reverse the
direction of the motor. If the drive is running when
+24 V DC is applied to terminal 19, it will follow the
ramp up and ramp down time settings to decelerate
the motor to zero speed and then accelerate it in
the reverse direction.
Description of choice:
Reversing [0]:
Choose if the ability to reverse the direction of rotation of
the motor is desired. No signal on terminal 19 will set up the
drive to run in the “forward” direction. 24 V DC from termi-
nal 12 to terminal 19 will allow reverse rotation. To run in re-
verse, in addition to the reverse signal at terminal 19, a
start command must be given to terminal 18.
The reverse function will reverse the direction of the motor
when its speed is controlled by the analog speed reference,
the jog speed reference or from “Local/Hand” mode. It has
no effect on rotation direction when using the digital refer-
ences of parameters 205 through 208.
Start with reversing [1], parameter 402, Start [0]:
Select if start and reversing are to be activated at the same
input. In effect, the switch to terminal 18 becomes a “start
forward” switch and the switch to terminal 19 becomes a
“start reverse” switch.
402 Terminal 18 (INPUT 18)
Value:
★
Start (START)
[0]
Latch start (LATCH START)
[1]
No operation (NO OPERATION)
[2]
External H-O-A (EXT. HOA AUTO)
[3]
Function:
Used for choosing between different possible functions of ter-
minal 18. Start and stop will be effected by the ramp times
selected in parameters 215 and 216.
Description of choice:
Start [0]:
Selected if a start/stop function is de-
sired. +24 V DC applied from terminal
12 to terminal 18 results in a start com-
mand. Removing the +24 V DC gives a
stop command. This is a “2-wire” con-
trol. The drive will start or restart as
soon as AC power is applied as long as
it is in the Remote/Auto mode with no
faults.
Latch start [1]:
Choose if a start and stop function is
desired for two different inputs, one
momentary input for start (terminal 18)
and one for stop (terminal 16, 17 or
27). If terminal 18 is connected to the
+24 V DC power source from terminal
12 for at least 20 msec., the drive will
start. In the illustration at the right, if terminal 16 is discon-
nected from the +24 V DC power source from terminal 12
for at least 20 msec., the drive will stop. This is a “3-wire”
control. The drive will not restart in remote mode after a
power outage. This is not normally used for unattended
HVAC applications.
No operation [2]:
Select if the drive is not to react to signals coming to termi-
nal 18.
If serial communication is used, the input status can be
read and used by the master.
External H-O-A [3]:
Selected if the H-O-A function is to be used externally from
the drive for switching between manual operation (Hand)
and the normal remote control (Auto). By energizing 24 V
DC from terminal 12 to terminal 17, the normal remote con-
trol mode is activated and normal control through the con-
trol terminals of the drive is possible.
