socomec ATyS C55 - Load shedding and HVAC Compressor

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EN
ATySController C55/65 - 549866C - SOCOMEC
14.2.5. Load shedding (C65 only)
ATyS C65 counts with 2 types of load shedding features:
- Forced load shedding: This type of load shedding will activate the LSC - Load Shedding Contact / Forced Shedding
output every time there is a transfer to the secondary source. The forced load shedding is used in cases where the load
power is stable and the secondary source provides less power than the normal/main source. The values to congure for this
function are the pre-transfer and post-transfer timers (by default, 4 and 1s respectively).
- Smart load shedding: A kVA limit can be set and when this limit is exceeded the controller can perform an automatic load
shedding in the same way than in the forced load shedding by activating an output (has to be congured as PTS - Power
Threshold Exceeded / Smart Shedding) that will go to the switching device opening the circuit for the non-essential loads
of the installation. The threshold and hysteresis dened will dene the activation/deactivation of this output. The main use of
this function is the same as before with the difference that if the load required power is variable in some cases it might not be
necessary to shed the loads when transferring to the secondary source and the controller will automatically detect the power
level and decide if to shed loads or not intelligently.
Note: for Smart load shedding it is necessary to use current transformers with the product. See chapter "9.3. Dual
Power Supply / Sensing", page 22.
14.2.6. Power up in auto
Enabling “power up in auto” will force the controller to start in automatic mode every time the controller recovers power (even
if mode before the power failed was manual). Set to "DISABLED" as standard.
14.2.7. DBT Timer in CTRL (C65 only)
In CONTROL mode (manually operating the switch through the controller buttons or via communications), this function will
force the controller to take into account the “dead band timer” when transferring from one source to the other.
14.2.8. HVAC compressor (C65 only)
This is a specic function designed to preserve the lifetime of the compressors inside HVAC units. When going back to
principal source position the contact will become active prior to starting the transfer (to shut down the compressor), then the
transfer will take place and then after reaching the opposite source, a congurable timer will elapse before deactivating this
output again. It avoids stressing the compressors in HVAC chillers.