Installation manual
CM-02-001
TYTANu DI Water Heater
O.I. 6/27/03 Installation, Operation and Maintenance Manual
ECO page 16
4.1.5 High Alarm:
The Digital Temperature Controller incorporates an independent alarm. The High Process Temperature Alarm prevents heater
operation above a preset maximum temperature that may harm the process and potentially the tank material. If the process
temperature exceeds the preset high alarm value, the heater will be disengaged. The temperature controller will activate once
the process temperature exceeds the set point by the preset value.
1. The high alarm value can be user defined in mode Level 1 Press the Display Key for less than one second to switch to the
parameter for alarm 1.
2. Press the up and down arrow keys to select the desired value.
4.1.6 Changing PID Constants:
Twenty-five percent (25%) attenuation is considered most appropriate for adjustment of the measured PID constants.
Depending on their use, the following circumstances may arise.
Ø When the occurrence of an overshoot poses no problem, the temperature of the controlled system can approach the set
temperature and become stable in a short period of time.
Ø When the occurrence of an overshoot is undesirable, a longer period of time should be allowed for the temperature of the
controlled system to approach the set temperature and become stable.
The PID constants measured under such circumstances may not be optimum for temperature control. In such case, the PID
constants may be changed or modified within their variable range. To change PID constants, turn the PID constant measuring
switch to the test position and then return it to the control position. This allows the controller to read the new PID constants. This
read operation may also be performed by turning the power to the temperature controller OFF and ON. If any process is
changed, recalibrate the temperature controller.
4.1.7 Measuring PID Constants:
The Temperature Controller has the capability of automatically tuning the PID parameters to fit the characteristics of the process.
The optimum PID parameters are automatically set by forcibly changing the Manipulated Variable (MV) to calculate the
characteristics (limit cycle method) of the control target. Depending on the auto-tune level selected, AT-1 or AT-2, the controller
will run this test at either 40% or 100% of the actual Process Set Point. When the auto tuning is complete, the appropriate PID
tuning parameters will be automatically installed into the non-volatile memory of the temperature controller.
1. Turn on water supply and set the desired water flow.
2. Turn on power to the temperature controller via the power switch.
3. Set the temperature controller's high set point setting to the desired operating temperature. This temperature must be at
least 36°F (20°C) above ambient.
4. Set the temperature controller's high alarm setting to the desired value. This is a deviation-type alarm that will operate
when the "displayed" temperature drifts above the set point plus this value.
5. Advance to the AT Parameter in mode Level 1using the Display Key.
6. Using the Up arrow key select “AT-2”. The controller will begin to perform its auto-tune test.
7. Press Display Key for 1 second to return to the beginning of Level 1 Mode. Press the DOWN Key to advance to Level 0
Mode, then hold display Key for 1 second to return to operating mode.
NOTE: While in the tuning mode, the “AT” auto-tune LED will flash.