TELEVAC MX4A, Инструкция по эксплуатации

Страница: 13 / 17

Instruction Manual MX4A Active Convection Gauge
(a) Address
(b) Baud Rate
(c) Stop Bits
(d) Parity
2.6 Analog Output
The MX4A provides the option for outputting the vacuum reading in an analog form. Operators who
wish to use PLCs to monitor processes should find this function useful. There are seven different
analog output formats to choose between. The formats include Logarithmic, Linear by Decade, Non-
linear, Linear 4, Linear 3, Linear 2, and Linear 1.
A . Logarithmic
The Logarithmic output is the most useful and accurate output for covering the entire range of
the 4A with an analog output. This format uses the formula below to convert the output voltage
into a pressure measurement:
Pr essr e
(
Tor r
) =
10
. 6 ×
(
Votge − 5
)
For example, a voltage reading of 3.075 Volts corresponds to pressure of .07 Torr.
10
. 6 ×
(
3 . 075 − 5
)
=
.
07
Tor r
B . Linear by Decade
The Linear by Decade output spans the entire range of the MX4A. It uses the units digit of
the voltage reading to communicate the decade of the pressure reading and the units after
the decimal to communicate the specific pressure using the very generalized expression below,
where A, B, C, and D are digits ranging from 0-9:
Votge
=
A.BCD → Pr essr e
(
Tor r
) =
10
A − 6
× .BCD
For example, a voltage reading of 8.367 Volts corresponds to a pressure of 36.7 Torr.
10
8 − 6
×
. 367
=
36 . 7 Tor r
C
.
Non-linear
The Non-linear option outputs the raw signal collected by the 4A sensor. The raw signal is
converted to the pressure using a many-point linearization process done by the MX4A. This
feature is used for diagnostic purposes.
D . Linear 4
The Linear 4 output is one of four linear outputs that cover a select range of the MX4A with a lin-
ear scale. The scale extends from .001 to 1 Torr, with each .010 Volt of the output corresponding
to .001 Torr.
Pr essr e
(
Tor r
) =
Votge ×
(
. 1
)
E . Linear 3
The Linear 3 output is one of four linear outputs that cover a select range of the MX4A with a lin-
ear scale. The scale extends from .01 to 10 Torr, with each .010 Volt of the output corresponding
to .01 Torr.
Pr essr e
(
Tor r
) =
Votge ×
(
1
)
F
.
Linear 2
The Linear 2 output is one of four linear outputs that cover a select range of the MX4A with a lin-
ear scale. The scale extends from .1 to 100 Torr, with each .010 Volt of the output corresponding
to .1 Torr
Pr essr e
(
Tor r
) =
Votge
×
(
10
)
G . Linear 1
The Linear 1 output is one of four linear outputs that cover a select range of the MX4A with a lin-
ear scale. The scale extends from 1 to 1000 Torr, with each .010 Volt of the output corresponding
to 1 Torr.
Pr essr e
(
Tor r
) =
Votge ×
(
100
)
email: sales@frederickscompany.com tel: +1 215 947 2500 web: frederickscompany.com mx4a_im rev L 12 of 16