MG14 operating manual Rev 1.4
21
Purpose of this interface is record of the measurement of the controller if needed. For channel
1 there are two analogue outputs
– one is a readout direct from the preamplifier and the second one
is the converted signal and filtered by the processor.
The first one solution allows for minimum response time as only is possible. However parallel with
this information the amplification range information must follow. Amplification range signals
( Range1,Range2 and Range3) are digital output with open collector OC type. For each amplification
range analogue outputs have almost the same voltage range. More details are shown in tab bellow
Vacuum range
measurement [Torr]
Output voltage
U
out
[V]:
Logical status on outputs
Preamplifier
Range1
Preamplifier
Range2
Preamplifier
Range3
P=U
out
/ (4x10
5
x Sg x Ie)
0,092 … 10
1
0
0
P=U
out
/ (4x10
8
x Sg x Ie)
0,092 … 10
0
1
0
P=U
out
/ (4x10
9
x Sg x Ie)
0,800 … 10
0
0
1
P=U
out
/ (4x10
11
x Sg x Ie)
0,000 … 10
0
0
0
where:
P
– pressure
U
out
– Output voltage ( proportional to the Ion current )
S
g
– sensitivity factor for gas g
I
e
– emission current
Second analogue signal for channel1 is converted with the following parameters:
Resolution :
22 bits
Full voltage range:
0-10V
Measuring and refresh rate:
25 s-1
Output impedance: 150 Ohm
Pin assignment
Fig. 3-10 I/O appliance socket (D-Sub, 9-pin)
1,2,3
GND
4,6
Analogue GND
5
Analogue Out for Channel 1 - linear signal direct from preamplifier
9
“Range1” digital signal – OC type
10
“Range2” digital signal – OC type