Short Circuit Monitoring; Commissioning; General Wiring Instructions; Fault Diagnosis Of Thermistor Function - Vacon optbj Safety Manual

vacon • 46
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
>= 1.5 sq mm
8.2.2

Fault diagnosis of thermistor function

The table below shows the normal fault / warning, generated when thermistor input is active
Fault code
29 Atex-thermistor
See the fault table in chapter 7.1.
8
3.
Maximum cable length without
short circuit monitoring. Shield
must be connected to the drive's lid
(PE).
X23 : OFF
1500 meters
Fault ID
280
Maximum cable length with short cir-
cuit monitoring.
X23 : ON
250 meters
Explanation
Atex-thermistor has detected
overtemperature.
Local contacts: https://www.danfoss.com/en/contact-us/contacts-list/
Thermistor function (ATEX)
Correcting measures
The resistance of thermistor
input must go below 2 kΩ to be
able to restart the drive.