How Regulation Works; Capacity Decrement And Regulation Stop; Capacity Limitation By Using Parameters Pmi And Pma; Dead Band Regulation - Emerson Dixell XC15CX Installing And Operating Instructions

It is possible to drive inverter with control signal of frequency or voltage (0-10 V DC) type.
NOTE: the analog output is not configurable. It may be frequency or voltage type depending on
the hardware.

16.2.1 How regulation works

a. The regulation starts when the value of the pressure/temperature of the suction line
increases and reaches the St1 value. If available, the inverter-controlled compressor
will start and be controlled from the PI-regulator.
NOTE: at the start-up the inverter-controlled compressor will be drived at maximum
power for SUt seconds in order to ensure proper lubrication.
b. Within the regulation band [SET-0.5*HY1 to SET+0.5*HY1] the capacity (speed) of the
inverter-controlled compressor will be modulated in accordance with the value of the
pressure/temperature variable and by using par. voS, when the pressure/temperature
is increasing, or by using par. vo2, when the pressure/temperature is decreasesing.
c. When pressure/temperature is higher than [SET+0.5*HY1] and the compressor is
already at is maximum possible capacity (speed), then another compressor (if
available) will be activated after expiring delay ton.
NOTE: if pressure/temperature goes over [SET+0.5*HY1] and the inverter-controlled
compressor is not available (due to safety delays 2on and 2oF or due to external signal),
another compressor will be activated (if available).

16.2.2 Capacity decrement and regulation stop

a. When the pressure goes below the value [SET-0.5*HY1] the inverter-controlled
compressor will be forced at the minimum allowable capacity for the time t1F.
b. After expiring the delay toF, the second compressor (if active when oA2=CP2) will be
deactivated and the inverter-controlled compressor will keep on working for interval of
time doF.
c. After the delay t1F expires, the inverter-controlled compressor will be stopped.

16.2.3 Capacity limitation by using parameters PMi and PMA

The compressor capacity can be limited both in maximum and minimum value by using par. PMi
and PMA as showed by the previous diagram:
-
PMi: (in percentage) set the minimum value for the compressor capacity.
-
PMA: (in percentage) set the maximum value for the compressor capacity.

16.3 DEAD BAND REGULATION

This kind of regulation is available only for ON-OFF compressors (oA1=CP1 and oA2=CP2)
and if par. rtY=db.
It uses a control variable (pressure/temperature) and a symmetrical band (par. HY1) around the
SETPOINT. When the control variable is within the band the outputs stay unchanged. When the
control variable is outside the band, the outputs will be enabled or disabled, respecting the delay
in activation (par. don, 2on) and deactivation (par. doF, 2oF) according to the following chart:
1592001530 XC15-35CX EN r1.2 11.04.2017 XC15-35CX 30/40