The pole contacts undergo wear due to the number of operating cycles with current and interrupted current during short circuits. It is recommended to check them at periodic intervals to decide whether the contacts must be changed or not. To avoid regular inspection of the contacts and the arc chute, the contact wear estimate helps with the planning of visual inspections based on the estimated wear (from 0% - new contact - to 100% - totally worn contact).
The contact wear increases every time the circuit breaker interrupts the circuit with or without current.
When the MicroLogic X control unit contact wear algorithm calculates a value which is above one of the predefined thresholds (60%, 95%, and 100%) an event is generated with an orange or red pop-up screen and corresponding event message.
Consult contact wear interpretation on EcoStruxure Power Device app in order to estimate the ability of the circuit breaker to isolate, carry rated current, operate, and trip:
oIsolate: Capability of the circuit breaker, once opened or tripped, to separate and isolate the circuit or a device from the rest of the electrical installation during maintenance or repair.
oCarry rated current: Capability of a circuit breaker to continuously carry its rated current without thermal runaway. It is recommended to limit the current load to 80% of its rated current to avoid accelerated aging of the circuit breaker.
oOperate and trip on overload: Capability of the circuit breaker to operate in normal or overload conditions. In overload conditions, the higher the overload current, the lower the number of remaining operations. Overloads occur on a healthy electrical circuit (for example, motor starting, or too many devices operating at the same time on a circuit).
oTrip on short circuit: Capability of the circuit breaker to operate in milliseconds to limit the consequences and/or the damage that may occur on the installation due to the thermal and electrodynamic effects of a short circuit between live conductors or between live conductors and earth.
Contact wear monitoring data is available as follows:
oOn the MicroLogic X display screen at Home > Maintenance > Health > Contact wear
oWith EcoStruxure Power Commission software
oWith the EcoStruxure Power Device app through Bluetooth or USB OTG connection
oOn the FDM128 display
oOn a remote controller using the communication network
The function generates the following events:
|
Code |
Event |
History |
Severity |
|---|---|---|---|
|
0x1440 (5184) |
Contact wear is above 60%. Check contacts |
Diagnostic |
Medium |
|
0x1441 (5185) |
Contact wear is above 95%. Plan for replacement |
Diagnostic |
Medium |
|
0x1442 (5186) |
Contacts 100% worn out. CB needs to be replaced |
Diagnostic |
High |
|
Code |
Event |
Recommended actions |
|---|---|---|
|
0x1440 (5184) |
Contact wear is above 60%. Check contacts |
Inspect visually the arc chute and main contacts at the next scheduled maintenance. |
|
0x1441 (5185) |
Contact wear is above 95%. Plan for replacement |
Plan to replace the circuit breaker. Consult contact wear interpretation on EcoStruxure Power Device app in order to estimate the circuit breaker ability to isolate, withstand rated duty, operate, trip. |
|
0x1442 (5186) |
Contacts 100% worn out. CB needs to be replaced |
Replace the circuit breaker. Consult contact wear interpretation on EcoStruxure Power Device app in order to estimate the circuit breaker ability to isolate, withstand rated duty, operate, trip. |
Contact your field service representative for more information about who can carry out the recommended actions.
