Glossary; Controller Display And Keys - BriskHeat MPC2 Mode D'emploi

Glossary

Alarm Output that trips when a certain
condition is reached, for example, a defined
temperature
Auto Tune Function that lets you calculate and easily set
the P, I and D parameters thanks to the
controller's self-learning.
Control output Output that controls the process and is
switched on and off as needed.
Hysteresis When, at a precise moment, the value of
the controlled quantity depends not only on
another reference quantity but also on the
values that the controlled quan- tity had
previously, there is hysteresis. Hysteresis
can therefore be considered inertia that
influences the control system, causing varia-
ble delays between the change of the refer-
ence quantity and the change of the con-
trolled quantity.
ON-OFF Control procedure based on activation and
deactivation of the output. For heating, the
output stays on until PV is less than SV by a
certain quantity (of- fset), and then stays off
until PV is not greater than SV by the same
quantity (or different quantity, depending on
controller configuration).
This type of control is not intelligent, does
not consider noise, and is not very accurate,
but ensures a limited number of switchings of
the output.
Overshoot Situation in which PV exceeds SV becau- se
the control action stopped too late. The ON
OFF controls have an overshoot greater than
the PID controls.
PID Acronym for Proportional-Integration-
Differentiation, indicating a system with
negative feedback, i.e., a device that ac-
quires a value from a process in input, com-
pares it to a reference value, and uses the
difference (error) to calculate the value of the
controller output varia- ble, which is the
variable that controls the process. The
output is controlled based on the current
value of the error (proportional action), on a
set of previous error va- lues (integral action),
and on the speed of change of the error
value (derivative action).
PV Acronym for Process Value, i.e., the value
that the process variable (temperature, valve
opening, etc.) has at that moment.
Programming Step A step is composed of a Setpoint
temperature, a ramp (or time required to
reach the temperature), and a hold/soak
(time period to maintain the temperature).
Solid state relay Also known as SSR, this is a relay desi-
gned specifically for frequent switching. It has
no moving parts or mechanical contacts, but
may still break or short circuit. This type of
relay is often used in tempe- rature control
systems such as PID.
®
© BriskHeat Corporation. All rights reserved.
MPC2 Digital PID Temperature Control Panel
Sensor Device that translates physical phe-
nomena (such as change in resistance based
on temperature) into electrical signals that can
be acquired and processed by the controller
Setpoint Set value (see SV).
SV Acronym for Set Value, i.e., the value that the
process variable (temperature, valve opening,
etc.) has to reach and maintain.
Thermocouple Sensor that transmits an electrical signal
of a few millivolts. Cannot be tested for galvan-
ic continuity. It needs specially de- signed
extension cables
Undershoot Situation in which PV does not reach SV
because the control action stopped too soon.
The ON OFF controls have an undersho-
ot greater than the PID controls.
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CONTROLLER DISPLAY AND KEYS

1. Temperature unit of measurement or number of program running.
2. State of outputs OUT1, OUT2, OUT3, OUT4.
3. Controller function states:

RUN = setpoint programmer active;

_/- = setpoint ramp active;

TUN = PID parameters tuning active;

MAN = manual/automatic (off = automatic control, on = manual control);

REM = remote setpoint enabled;

SP1/2 = setpoint active (off = setpoint 1, on = setpoint 2).

Work mode key (manual/automatic) in standard mode.
5. Up/down keys: raise/lower the value of the parameter displayed on the SV or PV display.
6. F key: lets you navigate among controller menus and parameters. Confirms the parameter value and
selects the next parameter.
7. Key pressed signals.
8. SV display: Setpoint Variable
9. PV display: Process Variable
Navigating the menus
The 4 keys are used for navigating the menus and submenus and for changing parameters and confirming
choices. Their function depends on the context and on how long they are pressed. L/R is used for the Auto-
tuning; * is not programmed.
The navigation functions assigned to the keys are:
At first power-on, scrolls the fast configuration menu; otherwise, the user configuration menu
(Setpoint, Alarm limits, Control output, etc.). Each time you press the key, the value of the
displayed parameter is confirmed and you go to the next menu item. Keep the key pressed
for more than 2 seconds to enter the Programming/Configuration menu.
Each time you press the key, you return to the previous menu item or to the higher menu
level, as appropriate. Keep the key pressed for more than 2 seconds to return to the Main
menu.
Press the key to enter a submenu or to reduce the value of the displayed parameter, as
appropriate. Keep the key pressed to progressively increase the speed of reduction of the
displayed parameter.
Press the key to raise the value of the displayed parameter. Keep the key pressed to
progressively increase the speed of raising the displayed parameter.
®
© BriskHeat Corporation. All rights reserved.
MPC2 Digital PID Temperature Control Panel
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