Why do you want them alternating? Just curious.
See my comment below.
IMO - you need a line for general alarm (inverted) and temperature 2 heater and therefore something like this
I would have thought because G5 & G6 use G4, and that G7 & G8 use G5 & G6, I would need to do it like you are showing below. Can you explain why I would need to do it this way? That's why I posted this question, to learn.
| Gate | Function | Input 1 | Input 2 | Time | Description in Profilux |
| 4 | AND | General Alarm INVERTED | Temperature 1 Heater | - | Heat OFF with ALARM |
| 5 | AND | G4 | Timer 1 | | |
| 6 | AND | G4 | Timer 2 | | |
| 7 | AND | General Alarm INVERTED | Temperature 2 Heater | | Heat OFF with ALARM |
| 8 | OR | G5 | G7 | | Heater 1 |
| 9 | OR | G6 | G7 | | Heater 2 |
I have done similar programming with two heaters there the second kicks in if the first does not manage to rise the temperature. Bu I do not use hysteresis for that - I set a different nominal value instead with the same hysteresis. The problem with your settings (IMO - I have not tested) will be that Heather 2 will run after Heather 1 have turned off. If that's not enough with heather 2 - temp will go down and heater 1 kick in again. It will be the hysteresis of Heater 2 that determines your temperature in the long run IMO.
I understand what you are saying, I will change the values on Temp 2 (virtual) as you have shown below.
I can see that you have discover the beauty of the pulse variable function. I have my heater in the same sump compartment as the temp sensor (around 35 l) Flow through it is around 2 500 l/h. Therefore - I have a short pause (30 sec) and rather long pulse (max 6 minutes)
My way of doing it would be something like this
2 Heaters
One runs 12:00 am - 12:00pm
Set to Timer 1
One runs 12:00pm - 12:00am
Set to Timer 2
2 Temp sensors
Temp 1
Normal Value 26.0
Cooling 0
Hysteresis 0.15
Operation mode controller
Control Pulse Variable
Off during Feed No
Pulse 00:10:00
Pause 00:01:00
Temp 2
Virtual
Normal Value 25,9
Cooling 0
Hysteresis 0.15
Operation mode controller
Control Pulse Variable
Off during Feed No
Pulse 00:10:00
Pause 00:01:00
The pulse and paus depends of your volume of sump apartment and the flow through it - you have to fine tune this. In this scenario - the sensor and heaters must be in the same apartment of the sump - otherwise there is a risk for boiling in that part there the heater is if flow disappear.
The temp probe and heaters are in the same area, but not to close to each other. I will adjust these as needed.
I would also have a 10 minutes delay for actual sockets if the contact with the main unit disappear and suddenly comeback
I do have this programmed.
Here is my DT temperature for the last month - nominal value 25 C - only 1 heather
Hope this will help you - I have not tested this - but maybe you get some ideas from it.
Sincerely Lasse