Sevcon Dragon8 - Digital (Contactor) Outputs

System design
Doc. # 177/52705
Rev. 1.0
53
The following table summarises the analog inputs and any special features:
Name
Pin
Usage
Analog Input 1a
K1
Input from external voltage source or 3-wire pot
wiper. Use pin H1 as supply for 3-wire pot.
Analog Input 1b
K2
Analog Input 2a
J1
Analog Input 2b
J2
Analog Input 3 (Motor
thermistor)
H2
Use for motor thermistor input or 2-wire pot input.
Has internal supply.
Table 20 - Analog inputs
Wire-off detection
Enable wire-off detection at 46C0h to 46C2h. For each input specify the allowable range of input
voltages. To disable, set the ranges to maximum.
Motor thermistor input
You can connect a thermistor sensor to the Motor thermistor input.
Type
Specification
PTC Silistor
Philips KTY83, PT1000 etc.
Table 21 - Motor thermistor input
To setup go to object 4620
h
:
• Configure as none, thermistor or CAN based thermistor
• Program the resistance / temperature profile in 461F
h
. This is an 8 point table which allows a
programmable thermistor table to be configured.
• For CAN based thermistors, the temperature can be loaded into object 4600
h
sub 16 using an
RPDO.
Read the measured motor temperature (PTC) or switch operation at object 4600
h
.
Digital (contactor) outputs
There are 2 digital outputs which can be used to control loads such as contactors, horns, lights, etc.
Error control
It is important that analog outputs on nodes other than the master must have appropriate error
configuration to protect against CANbus faults. This section explains how to configure the
outputs to go to a safe state in the event of a CANbus fault. It is the installer’s responsibility to
define what a safe state is for each output.
In a CANopen network, the slave node on which the analogue (contactor) outputs is different to the
VCU node which calculates the output value. If the CANbus fails, the VCU is no longer able to control