Danfoss VLT HVAC Drive Instruction Manual page 57

VLT ® HVAC Drive Instruction Manual
[Off]
key on LCP
If no external stop function is selected, and the [Off] key is inactive, the motor can be stopped
by disconnecting the line power supply.
[Auto on]
or serial communication. When a start signal is applied to the control terminals and/or the bus,
the adjustable frequency drive will start. The key can be
[Auto on] key on LCP
[Reset]
Enabled
5.1.4. RS-485 Bus Connection
One or more adjustable frequency drives can
be connected to a controller (or master) using
the standard RS-485 interface. Terminal 68 is
connected to the P signal (TX+, RX+), while
terminal 69 is connected to the N signal (TX-,
RX-).
If more than one adjustable frequency drive is
connected to a master, use parallel connec-
tions.
In order to avoid potential equalizing currents in the shield, ground the cable shield via terminal
61, which is connected to the frame via an RC link.
Bus termination
The RS-485 bus must be terminated by a resistor network at both ends. If the drive is the first on
the last device in the RS-485 loop, set the switch S80 on the control card for ON.
For more information, see the paragraph
stops the connected motor. The key can be
.
enables the adjustable frequency drive to be controlled via the control terminals and/
.
NOTE
An active HAND-OFF-AUTO signal via the digital inputs has higher priority than the
control keys [Hand on] [Auto on].
is used for resetting the adjustable frequency drive after an alarm (trip). The key can be
Disabled
[1] or [0] via par. 0-43
MG.11.A4.22 - VLT ® is a registered Danfoss trademark
5. How to operate the adjustable frequency
Enabled [1] or Disabled
Enabled
[1] or
Reset Keys on LCP
.
Illustration 5.6: Connection example.
Switches S201, S202, and S801
drive
[0] via par. 0-41 [Off]
Disabled
[0] via par. 0-42
.
5
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