INFICON HPG400-SD ATM to High-Vacuum Gauge (DeviceNet) User Manual
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tira03e1-b (0310) BPG/HPG400-SDv1.cp
The setpoints can only be read by DeviceNet. It is not possible to set the
values or to influence the state of the relays by DeviceNet. Even if the de-
vice is not allocated, the relay status is set corresponding to the voltage ad-
justed by the two setpoint potentiometers.
Only in case of a microcontroller RESET (for example reset on Identity Ob-
ject), the relays will be reset too.
The setpoint is available in the actual pressure unit and data type. If the pressure
unit "Counts" is set, use the following formula for the conversion from Counts to
pressure:
BPG400-SD:
p
mbar
=
10
Counts / 2000 - k
where:
k
mbar
=
12.5
k
Torr
=
12.624903
k
Pa
=
10.5
The relation between setpoint and voltage is:
p
mbar
=
10
(U - 7.75) / 0.75 + c
where:
c
mbar
=
0
c
Torr
=
-0.125
c
Pa
=
2
HPG400-SD:
p
mbar
=
10
9 × Counts / 1024 - 6
The relation between setpoint and voltage is:
p
mbar
=
10
9 × U / 10 - 6
The setpoints are only activated, if the pressure is below 100 mbar, therefore a
setpoint above 100 mbar can not be realised.
The S-Analog Sensor Object provides the following Common Services:
Service
Code
Service Name
Description of Service
0E
h
Get_Attribute_Single
Returns the contents of the specified attribute.
10
h
Set_Attribute_Single
Modifies an attribute value.
Service
Code
Service Name
Description of Service
4C
h
Full Scale Adjust
Performs a Full Scale Adjust for the Pirani
There are no state transitions associated with the invocation of this service. It is,
therefore, incumbent upon the user to establish the device into the desired con-
figuration prior to, and during the execution of this service. This will generally in-
volve exposing the sensor to a known environment and treating the values read
during execution of the services accordingly.
A success service response indicates that the service was accepted and the ap-
plication process started.
2.4.3 Common Services
2.4.4 Object-Specific
Services on Instance 1 /
Pirani