contact wear algorithm in TeSys Giga controllers continuously calculates the remaining service life of the contacts. When the remaining life is below 15%, an alert is issued, enabling preventative maintenance to be scheduled: ■ A local alert is visible on the Diagnosis LED on the front of the contactor. ■ An optional RWD module can be used with advanced contactors.
1.05 x Ir
1.2 x Ir
1.5 x Ir
7.2 x Ir
Class Time to trip from a cold start
10A >2 hrs
<2 hrs
<2 min 2 s < to < 10 s
20
>2 hrs
<2 hrs
<2 min 2 s < to < 10 s
20
>2 hrs
<2 hrs
<2 min 2 s < to < 20 s
30
>2 hrs
<2 hrs
<2 min 2 s < to < 30 s
Table 1: Examples of thermal overload relay classes based on rated current (Ir). (Table source: Schneider Electric)
Control Voltage Diagnosis
The control voltage monitors for undervoltage and overvoltage conditions. The diagnosis indication is remotely available on units with part numbers ending in LSEMC using an optional remote device management (RDM) module. An undervoltage is defined as a supply voltage below 80% of the minimum specification, and an overvoltage is defined as greater than 110% of maximum.
amount of time it takes for the relay to open when there is an overload. There are also differences between North American and IEC trip classes. For example, class 10 is a North American trip class that trips the overload within 4-10 seconds of detecting 600% of the overload current setting. Class 10A is an IEC trip class that trips the overload within 2-10 seconds of detecting 720% of the overload current setting (Table 1). Trip classes 10A and 10 are suited for normal-duty motors. Class 20 is recommended for heavy-duty motors to avoid nuisance tripping. Class 30 is used with a very long starting motor.
use of MPSDs is also an important consideration to ensure maximum productivity and availability. In IEC 60947-4-1, MPSD refers to a device designed with a delay to protect a motor from overload conditions. A second type of device, an IMPSD, is a specific type of MPSD that trips immediately upon detecting an overload. IMPSDs are not usually associated with AC motor protection. Depending on the application, motor starting can take a few seconds or several tens of seconds. The MPSD must be specified to meet the application requirements for safety while avoiding nuisance tripping. To satisfy specific application needs, IEC 60947-4-1 defines several classes of overload relays. The trip class indicates the maximum
Internal Functioning Diagnosis
Continuous blinking of the Diagnosis LED indicates any internal malfunction of the control circuitry.
Motor protective switching devices Smart motor controls like TeSys Giga contactors are an important part of Industry 4.0 installations. The
TeSys giga overload relays
TeSys Giga thermal overload relays are highly flexible and designed
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