Emerson EV3 Series, Инструкции по применению

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AGL_Sol_EV3_E_Rev_01 21
Reasons for moving to the Speed-Drop Protection mode:
▪
Overtemperature of the power module
▪
Overtemperature in the discharge line
▪
Operating in field weakening range
▪
Output overcurrent
▪
Input overcurrent
▪
Drive ambient temperature foldback
The controller can avoid moving to the Speed-Drop Protection mode by using registers [37], [40],
[41], [42], [43], [44], [45] and [110] for control purposes.
6.2 Power module speed-drop protection
Considering the described speed-drop protection behaviour, the logic for the power module
protection follows the diagram below:
Figure 13: Power module speed drop protection logic
If the temperature reaches 108
o
C, the drive will take over the speed demand and will reduce it to the
speed-drop protection speed, in an attempt to reduce the module temperature.
If the speed reaches its speed-drop protection value, and the temperature is still above 108
o
C for
30 seconds, the drive will automatically shut down the compressor.
However, if the temperature decreases below 108
o
C, the drive will enter in the Speed Holding area,
where the speed is kept constant, until the temperature goes below the recovery value, ie, below
103
o
C.
If the temperature goes below the recovery value, the drive will return to the speed commanded
initially.
6.3 Discharge line temperature protection
If a discharge line temperature sensor is wired and activated via register [207] the drive will control
this temperature. This is achieved via the DLT value [77] considering a lower speed-drop protection
limit readable via register [46] or configurable via register [110] and an upper maximum limit [27].
Once the drive goes into speed-drop protection mode the functionality is the same as described in
Chapter 6.1
" Speed-Drop Protection mode " .
Limits Register Default values
Trip limit [27] 135
o
C
SDP limit [46] 130 o C
SDP recovery
threshold
- 125
o
C
Table 18: DLT speed-drop protection temperatures
NOTE: The discharge line temperature speed-drop protection can be disabled through
register [232]. In this case the drive will shut down the compressor immediately when
exceeding the upper limit.