The cyclic changeover will balance the runtimes of the connected heat generators.
The cyclic changeover uses an internal communication signal which will be automatically connected.
ATTENTION:
When a heat generator’s position number is in the cyclic changeover range, it shall have a minimum runtime SYS-04 different of „0“.
If the heat generator runtime is set to the value “0”, it will decrease its position number during every cyclic changeover and finally reach the first position and stay there.
Each heat generator has a position number, defined by parameter SYS-01, which is used for cyclic changeover. When a heat generator exceeds its maximum runtime, defined by parameter SYS-04, this module starts a procedure to become the last heat generator in the group. All the following heat generators will automatically decrease their position number by one.
ATTENTION:
The cyclic changeover occurs immediately when the hours run are exceeded if one of the following conditions are true:
If the cyclic changeover conditions are not fullfiiled till 1:00 o’clock:
Example: Cyclic changeover
For three boilers in the cyclic changeover, set the changeover sequence of the strategy CYC-01 to 0103 (numbers 1 and 3).
Initial situation
Heat generator |
Position number |
Max hours run |
Actual hours run |
Boiler A |
1 |
200 |
90 |
Boiler B |
2 |
100 |
70 |
Boiler C |
3 |
150 |
30 |
Boiler D |
4 |
Does not care |
Does not care |
After 30 hours boiler B reaches its maximum hours run assuming that all 3 boilers being switched on during that time.
Boiler B will initialize the cyclic changeover:
After 30 hours before cyclic changeover:
Heat generator |
Position number |
Max hours run |
Actual hours run |
Action |
Boiler A |
1 |
200 |
120 |
None |
Boiler B |
2 |
100 |
100 |
position number to end of sequence; reset hours run |
Boiler C |
3 |
150 |
60 |
decrement position number by one |
Boiler D |
4 |
does not care |
does not care |
After 30 hours after cyclic changeover:
Heat generator |
Position number |
Max hours run |
Actual hours run |
Boiler A |
1 |
200 |
120 |
Boiler B |
3 |
100 |
0 |
Boiler C |
2 |
150 |
60 |
Boiler D |
4 |
does not care |
does not care |
Table 22. Parameter List
Description |
Value Range |
Default Value |
Unit |
SYS-01: position number |
1...16 |
1 |
- |
SYS-04: maximum boiler runtime |
0...1E6 |
100 |
h |