23
www.eltherm.com
23
www.eltherm.com
Control of an external power contactor (proportional
control)
The load contact is open at ambient temperatures above the
setpoint (P10)
At ambient tempatures below the entered minimum am-
bient temperature (P41) + 1/6 of the difference between
the setpoint (maintaining temperature) and the minimum
ambient temperature, the load contact is closed. At ambient
temperatures in between, the controller runs in cycle mode.
The output level P05 is used as the basic display.
Structure switch settings
No.
description
selection option
S01
Selection actual
value 1 (X1)
[1] = Pt100, 3-wire (AE1)
2 = Pt100, 2-wire (AE1)
3 = thermocouple type J (AE1)
4 = thermocouple type K (AE1)
5 = voltage input (AE3)
6 = current input (AE3)
S02
Selection actual
value 2 (X2)
5 = voltage input (AE4)
6 = current input (AE4)
S03
Select setpoint W
5 = external setpoint (AE4)
S04
Selection of output
function controller
4 = continuous control
S05
Selection swit-
ching output
3 = analog output clocked
Parameters used
No. description
factory
setting
Own
setting
P01 Input variable X1
Display only
P03 Reference variable W
Display only
P04 Current display
Display only
P05
output level at the proportional
controller/ steady controller
Display only
P11 Switching hysteresis
2
P12 min. standstill time K1
0
P15 sensor correction 1
0
P16
Over temperature alarm 1
999
P17 low temperature alarm 1
-99
P18
Lower analog scaling value
(0/2V, 0/4mA)
0
P19
Upper analog scaling value
(10V, 20mA)
100
P28
power monitoring
load output
0
P75
Low Level mode analog inputs/
outputs
0
P76
min. output signal analogue
output
0
P77
max. output signal analogue
output
100
External setpoint with continuous output
The actual value x is recorded via a temperature sensor or a
standard signal and converted into a digital signal. Before this
signal is sent to the controller, the actual value is corrected.
The corrected actual value is shown on the display.
The setpoint w comes from an external source as a standard
signal (0/4 to 20mA or 0/2 to 10V) and is converted into a digi-
tal signal. The converted value is shown on the display.
The size of the output signal can be limited by a minimum
and maximum value on the controller.
The hysteresis h is set on the controller. When controlling with
a continuous output, the hysteresis indicates the range in
which the output signal varies between 0/4mA and 20mA or
0/2V and 10V.
The control difference x
d
= w - x is formed in the controller..
If the control difference is x
d
< h, the output emits a signal up
to 20mA or 10V.
If the control difference is x
d
≥ h, the output emits a signal of
20mA or 10V.
If the control difference is x
d
< 0, the output emits a signal of
0/4mA or 0/2V.
