Vacon optbj, Safety Manual

Page: 46 / 47

8
vacon • 46 Thermistor function (ATEX)
Local contacts: https://www.danfoss.com/en/contact-us/contacts-list/
8.1.4 Short circuit monitoring
The thermistor inputs TI1+ and TI1- are monitored for short circuit. If a short circuit is detected, the
drive modulation is disabled within 20ms, Fault 30, Safety diagnostic (subcode 522) is generated.
When the short circuit has been removed, the drive can be reset only after restarting the drive.
The short circuit monitoring can be enabled or disabled using the jumper X23 in ON or OFF position
respectively. The jumper is set in ON position by factory default.
8.2 Commissioning
NOTE! Installation, testing and service work on the OPTBJ board can be performed only by qualified
persons.
NOTE! It is not allowed to perform any repair work on the OPTBJ board. Return faulty boards to the
manufacturer for analysis .
NOTE! It is recommended to test the ATEX functionality using thermistor input on OPTBJ board pe-
riodically (typically once a year). For testing, activate the thermistor functionality (e.g. remove Atex-
thermistor plug from the OPTBJ board). The drive enters to fault state and indicates fault 29 (Atex-
thermistor fault, subcode 280).
8.2.1 General wiring instructions
The thermistor connection must be done using a separate control cable. It is not allowed to use
wires belonging the motor supply cables or any other main circuit cables. A shielded control cable
must be used. See also Chapter
3.
8.2.2 Fault diagnosis of thermistor function
The table below shows the normal fault / warning, generated when thermistor input is active
See the fault table in chapter 7.1 .
Maximum cable length without
short circuit monitoring. Shield
must be connected to the drive's lid
(PE).
X23 : OFF
Maximum cable length with short cir-
cuit monitoring.
X23 : ON
>= 1.5 sq mm 1500 meters 250 meters
Fault code Fault ID Explanation Correcting measures
29 Atex-thermistor 280
Atex-thermistor has detected
overtemperature.
The resistance of thermistor
input must go below 2 k
Ω
to be
able to restart the drive.