STAUFF LPM-II-plus, Руководство пользователя

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As a policy of continual improvement, STAUFF reserves the right to alter the specification without prior notice.
201.031 Date of Issue: 06 November 2018
6.1.2.4 Switched Input and Output Signals
The LPM has one switched input and two switched outputs. These can be used instead of, or in addition
to, the RS485 interface for command and control. The RS485 interface is more flexible but requires more
software work if LASPAC-View is not used (e.g. control from a PLC). An alternative is to control the LPM
via these switched I/Os, either from a PLC or using a manual switch and indicators.
Figure 6.6 Switched I/O Signals
In order to reduce wiring the input and outputs all connect together on one side (see Figure 6.6).
However they are optically isolated from the rest of the system so can be used to switch unrelated
signals.
6.1.2.5 Start Signal
The “start signal” is an opto-isolated input that can be used to start a test, it can be used to ensure
testing only occurs when the hydraulic system is running. For example, the start signal could be wired to
go on and off with the main hydraulic pump or with a solenoid valve that allows fluid flow. That way the
log does not fill up with invalid tests that were carried out with no flow.
This could be from a push button or a PLC output. The input accepts AC or DC signals, typically derived
from the DC supply voltage. The exact function of this input is determined by the Test Mode setting
(section tbc).
Item Minimum Maximum
Voltage 9V DC 36V DC
Impedance 10k Ohms

When the START signal transitions from OFF to ON, the unit will start a new test or restart any
test in progress.
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At the end of the test, the state of the START signal is checked
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If the START signal is still on at the end of a test, another test is started. So that testing continues
while the START signal is held on.
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The switching off of the start signal will operate as a STOP command. That is, it will abort any
test in progress. It will continue to show and report the previous result.

This new operation mode applies whether or not continuous testing is enabled.