Shanghai Hanshi Electric Agent Product Technical Information;

1、 Background of on-site case studies

A certain customer is usingSchneider EOCR-I3M420When protecting the device, the locked rotor protection parameter was foundSC can only be adjusted to 7（According to the operation manualSCThe setting range is 2-8），On site settingOvercurrent value OC=33AThe customer suspects equipment malfunction. According to technical analysis, this is a normal logical limitation and is related to the internal protection mechanism of EOCR.

2、 Analysis of Working Principle

In the EOCR series,Blocking protection multiple SCis based onOvercurrent value OCThe multiple setting is used to detect the locked rotor state of the motor caused by mechanical jamming, abnormal load, etc. during startup or operation. However, in order to prevent misoperation and hardware overload, the controller dynamically limits the upper limit of SC:

thus it can be seen:The larger the OC value, the smaller the upper limit that SC can be set(Because the product of the two is limited);

　　The smaller the OC value, the wider the range of multiples that can be set.

3、 Example Description

The on-site equipment parameters are as follows:

Model: EOCR-I3M420 (OC80 range) OC=33A

Calculation: 240 ÷ 33=7.27 SC_ {max}=7

Therefore, the actual adjustable range is2 to 7 timesThe SC on the panel cannot be set to 8, which is a normal design.

4、 Conclusion: EOCR stall protection (SC) is not a separately set parameter, but is subject toOvercurrent setting value (OC)Dynamic multiples of restrictions.

In practical applications, when it is found that SC cannot be set to 8, priority should be given to checking whether the OC value is large.

This linkage mechanism is the intelligent protection logic of EOCR, which ensures that the device operates within a safe range.