ABB eVM1, Инструкция по установке и обслуживанию

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14.7.3.4 Number of Starts
A protection function supervises the number of starts of all the available protection functions. It is
particularly significant for motors where it is also important to distinguish between cold starts and
warm starts, the allowable number of which is generally provided by the motor manufacturer.
Motor temperature estimated by the Thermal Overload protection is used to determine whether a
start is cold or warm. When the thermal overload function is not instantiated, a cold start is
assumed and warm start parameters are dimmed and not available.
After the Reset Time (T rst) has elapsed the counted number of starts is decreased by one.
If the preset number of warm (or cold respectively) starts is reached, the start signal of the
protection function is activated.
If there is another start, the protection function trips.
Number of Starts : N° of cold starts, below temperature threshold Tws, declared
by the Motor manufacturer.
Number of Warm Starts (Nws): N° of warm starts, above temperature threshold Tws,
declared by the Motor manufacturer.
Temperature of Warm Start (Tws): Above Tws temperature threshold a start is assumed to
be “warm”.
Reset Time (t rst): Cooling down motor time; time to dissipate the heat of a
motor start.
Source of Number of Starts: By checking the respective box the starting signal arising
from any active protection function ticked is used to count
starts.
Fig. 73