Air and Water cooled inverter chillers and heat pump
D-EOMZC00105-17EN
Operation Manual
12/84
EWAD TZ - EWAD TZ B -EWWD VZ
Air and Water cooled inverter chillers and
heat pump
1.6.11 Evaporator Pump Start
A 24 Vdc digital output (with internal supply) is enabled when a pump (#1 or #2) is required to start. The output
can be used to start an external pump (either at fixed or variable speed). The output requires an external input
or relay with less than 20 mA excitation current.
1.6.12 Condenser Pump Start (W/C units only)
A digital output is enabled when a pump (#1 or #2) is required to start. A pump will be required to start when a
compressor will be called to start.
1.6.13 Demand limit
This optional function can be used to limit the unit capacity percentage to a changeable limit value. This
limitation cannot be directly linked to a corresponding limitation of the unit current (50% demand limit can differ
from 50% of the unit FLA).
The demand limit signal can be changed continuously between 4 and 20 mA. The Microtech III will convert
this signal into a unit capacity limitation changing between minimum capacity and full capacity with a linear
relationship. A signal between 0 and 4mA will correspond to a full unit capacity, in this way if nothing is
connected to this input no limitation will be applied. The maximum limitation will never force a unit shutdown.
1.6.14 Setpoint override
This input allows to apply an offset on the Active Setpoint to adjust the operating point of the ELWT. This input
can be used to maximize the comfort.
1.6.15 Pump VFD Signal (A/C units only)
The “Pump VFD Signal” terminals are available for pump inverter kit option when factory wired speed reference
is required. These terminals are placed inside the main electrical panel. For more information about this option
see 7.4.