62
20.2
Cascade Parameters
Once all the cascade wiring has been completed as per chapter 20.1, before giving the master heat pump a heat
demand, the following parameters within all heat pumps will need set:
Parameter
Description
Default Setting
Unit
3
5 1 0
Lead Strategy
Late on, late off
3
5 1 1
Output Band (Min)
0
%
3
5
1
2
Output Band (Max)
100
%
3
5 1 4
Stage Sequence
Serial, release last stage
3
5 1 6
Max Sources Force Charge
4
3
5 1 7
Max Source Force Charge OT
-
°c
3
5 1 8
Number Source Defrost Allowed
1
%
3
5 3 0
Release Integral Source Sequence
100
°c*min
3
5 3 1
Reset Integral Source Sequence
20
°c*min
3
5 3 3
Switch on Delay
5
Min
3
5 3 8
Substitute Common Flow Temperature
Highest Source Value
3
5 4 0
Auto Source Sequence Change Over
500
Hrs
3
5 4 1
Auto Source Sequence Exclusion
None
3
5 4 4
Leading Source
Source 1
3
5 9 0
Temperature Differential Min
-
°c
A C S
Neutral Zone Heating Cascade
4
°c
20.2.1
L
EAD
S
TRATEGY
(3510)
The four available options are:
1.
Late on, early off
– Additional generators are switched on as late as possible (Output band max) and
switched off again as early as possible (Output band max) to have the smallest number of generators in
operation, or to obtain short running times for additional generators.
2.
Late on, late off - Additional generators are switched on as late as possible ("Output band max") and
switched off again as late as possible ("Output band min"); in other words, the generators operate with the
smallest possible number of switching cycles.
3.
Early on, late off - Additional generators are switched on as early as possible ("Output band min") and
switched off again as late as possible ("Output band min") to have the largest possible number of generators
in operation, or to obtain long running times for additional generators.
4.
According to buffer temp - The generators are switched on and off depending on the storage tank
temperatures. If the temperature at all sensors (B4, and B41) lies below the required flow temperature, the
control system releases the first generator stage. Additional generator stages are released every time the
set switch-on delay time has elapsed.
20.2.2
O
UTPUT
B
AND
M
IN
&
M
AX
(3511
&
3512)
The values are used as switching on/off criteria according to the selected lead strategy.
20.2.3
S
TAGE
S
EQUENCE
(3514)
There are 3 available options, but the 1 option that is designed for heat pump cascade is detailed below:
1.
Serial, release all 2nd stage = Designed for gas and oil boilers.
2.
Parallel, release last stage = Designed for condensing boilers.
3.
Serial, release last stage = Designed for heat pumps in cascade.
With this sequence of stages, every generator is released with its basic stage first and then with its second
stage/modulation stage, in accordance with its priorities. The stage/modulation stage released last is the
only stage given release of control. This means:
i)
Only the output stage switched on last may switch on/off according to the setpoint and the
generator’s temperature.
ii)
Modulating generators may provide control with their modulation stage.
20.2.4
M
AX
S
OURCES
F
ORCE
C
HARGE
(3516)
Defines the maximum permissible number of generators used for forced charging. The number of released generators
also depend on the attenuated outside temperature (see setting below, line 3517).
Содержание S-ASX 30
Страница 2: ...2 ...
Страница 24: ...24 10 CORRECTIVE FACTORS 10 1 Heating Performances ...
