VEGA VEGASEL 643 - Manual (Page 12)

12 VEGASEL 643
Set-up
Double point control
With a double point control it is possible to generate
switching signals at two different points of the input
signal (0/2 … 10 V or 0/4 … 20 mA).
Procedure
• Adjust the coded key with different values.
• Possible adjustment range 1 % … 99 %.
• As example min. = 20 %, max. = 60 %, with this
adjustment there is a hysteresis of 40 %.
• The auxiliary level switch is hence ready for opera-
tion. Please cover with the transparent cover (15).
Note:
Adjust the percentage values with the coded keys
which relate to the input signal.
Example 1
- Voltage input 0 … 10 V
- Two-point control
- Switch points min. = 20 %, max. = 60 %
0 … 10 V corresponds to 0 % … 100 %, ∆ = 10 V
20 % of 10 V = 2 V
60 % of 10 V = 6 V
Switch point 20 % corresponds to 2 V
Switch point 60 % corresponds to 6 V
Example 2
- Voltage input 2 … 10 V
- Two-point control
- Switch points min. = 20 %, max. = 60 %
2 … 10 V corresponds to 0 % … 100 %,
∆ = 10 V – 2 V = 8 V
20 % of 8 V = 1,6 V
60 % of 80 V = 4,8 V
Switch point 20 % corresponds to 1,6 V + 2 V = 3,6 V
Switch point 60 % corresponds to 4.8 V + 2 V = 6,8 V
Example 3
- Current input 0 … 20 mA
- Two-point control
- Switch points min. = 20 %, max. = 60 %
0 … 20 mA corresponds to 0 % … 100 %, ∆ = 20 mA
20 % of 20 mA = 4 mA
60 % of 20 mA = 12 mA
Switch point 20 % corresponds to 4 mA
Switch point 60 % corresponds to 12 mA
Example 4
- Current input 4 … 20 mA
- Two-point control
- Switch points min. = 20 %, max. = 60 %
4 … 20 mA corresponds to 0 % … 100 %,
∆ = 20 mA – 4 mA = 16 mA
20 % of 16 mA = 3,2 mA
60 % of 16 mA = 9,6 mA
Switch point 20 % corresponds to 3,2 mA + 4 mA =
7,2 mA
Switch point 60 % corresponds to 9,6 mA + 4 mA =
13,6 mA
The calculation and information examples are valid in
the same way for the single point control.
t
60
%
100
0
20
12 13 14
12 13 14
Coded key
max. 60
^ Hysteresis
40 %
min. 20
Mode A
Mode B