OI_EC2-XC645CX_A1_A2L_A3_EN_Rev01_866933.docx EC2-XC645CX
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Regulation Start: increasing capacity
a. The regulation starts when the suction pressure (temperature) increases and reaches the
value
SET-Pbd/2+(Pbd*PM)/ 100
. At first, if available, the digital compressor is powered, and
it is modulated in PWM mode.
NOTE:
At start up the valve is energized for SUt seconds.
b. Within the adjustment range (
SET–Pbd/2
-
SET+Pbd/2
) the digital scroll compressor is
activated in PWM mode in accordance with the value of the control variable.
NOTE:
When the TRIAC is on the compressor is discharged; when the TRIAC is off the
compressor is operative).
c. When the pressure is greater than
[SET + Pbd/2]
and the TRIAC output is already at
maximum, another compressor is started after the “ton” delay time.
d. Then, if additional capacity is required (pressure higher than
[SET + Pbd/2]
another
compressor starts after the “don” time.
NOTE:
If the pressure exceeds the value
SET+Pbd/2
and the DGS compressor is not available
(blocked by onon, oFon, safety digital input), another compressor is started (if available)
in order to meet the adjustment request.
Decreasing capacity and regulation stop
a. When the pressure is lower than
[SET - Pbd/2]
, the DGS compressor is still modulated to
minimum capacity for the toF time.
b. At the end of the toF time the load with more working hours is shut down. If the load must
stay on because the donF time is not over yet, the next load is considered, and so on until a
load that can be shut down is found or becomes available.
c. This procedure continues with all active loads, with the shutdowns spaced out by the doF
time setting.
d. When only the DGS remains on, at the end of the doF time the DGS is shut down too.
Summary of Contents for EC2-552
Page 1: ... EC2 XC645CX v 3 5 ...
