ATR121 Control of two stage heater

user17927 · Post by **user17927** » 13/09/2018, 18:59

We are using the ATR121 to control a fuel driven heater with two power stages (High Low Off). We would like the high output (out2) from the controller to be active until the temperature is 2°C below the set value, the low output (out1) should be active until the set value is reached. Out1 should be activated again when the temperature goes below the hysteresis (5°C). If the temperature goes below 2°C lower than the set value out2 should be activated again. We made this by setting different temperature values on out1 and out2 and different hysteresis but then the operators needs to be careful how they are are setting up the temperatures. Is there a way of setting just out1 and have out2 follow 2°C below?

The heater only runs if out1 is on so it dosn't matter if out2 is on before out1.

Post by **Pixsys tecnico 6** » 14/09/2018, 8:45

Hi,
please can you post your parameter list so we can check it for your application?

Best regards.

user17927 · Post by **user17927** » 14/09/2018, 9:50

Here it comes:

01 c.ou - o1.2
02 SEn - ntc
03 d.P. - 0.0
04 Lo.S - 5
05 Hi.S - 30
11 rEG. - HEA
14 HY.c - 5
19 AL. - A.A
20 c.r.A - n.c.S
23 HY.A - 3
28 Fnc - d.SE

Setpoint 1: 20°C
Setpoint 2: 18°C

Thees are the parameters I have made changes to, this works but the user needs to adjust setpoint 1 two degrees higher to make the system work properly. The best thing wold be to have setpoint 2 following setpoint 1 but two degrees lower.

Best Regards

Joel

Post by **Pixsys tecnico 6** » 14/09/2018, 12:38

Hi,
parameter list attached.

How to ATR121 works using this parameter list:

SET1 --> this is the command setpoint and the user can change it. The OUT 1 is open over this setpoint value and it is close under the Setpoint value - its hysteresis.

SET2 --> this is the AL Setpoint and the user doesen't need to change it. (If you want lock this setpoint, please set 25.[PSE] = "PrA"). OUT2 is always closed under the value of the SET1 - SET2.

Best regards

acegree · Post by **acegree** » 03/02/2019, 12:15

my manual old style heater blower seems to work off and on, what would be the problem? thanks

Post by **Pixsys tecnico 6** » 04/02/2019, 10:10

Hi,
maybe the problem is the Hysteresis of the OUT1 and the OUT2. Can you try Set their value to 1 (HY.c and HY.A). How are you using the ATR121 output? What did you connect to the OUT1 and OUT2?

Best Regards.

Pixsys Forum