1 3
TRM138
The conversion is made under the linear
law in a specified variation range of the input
value in accordance with lower and upper
limits set in parameters
Ao.L (PL2)
and
Ao.Н (PL2)
accordingly.
DAC’s output characteristics in the
registration mode are presented in Figure 9.
3.2.6 Output Units
3.2.6.1. Output units (OU) are designed
to synchronize actuating signals generated
by LUs with the operations of the peripherals
engaged in regulating the facility’s
parameters or monitoring its status.
Depending on version, the instrument
can be equipped with a number of OUs
varying in purpose and operation mode: key
type (electromagnetic relay assemblies,
transistor or triac optocouples) analog type
(digital/analog converters “parameter
current”).
Connection diagrams for TRM138 with
various OUs are presented in
Appendix 2
.
3.2.6.2.
Key type OUs
are used to
control final actuating devices (heaters,
blowers, etc.) either directly, or through
control starting units with a higher
commutation capability (power starters,
contactors, thyristors, triacs, etc.) under the
positional law – “activated deactivated”.
3.2.6.3. In TRM138R instruments
electromagnetic relay assemblies
are
used as OUs. These relays’ normally open
contacts are led out to exterior junction
terminals. To increase relays’ service life
their contacts (especially at commutation of
inductive loads) are recommended to be
connected in parallel with spark protection
RC circuits (Figure 10).
3.2.6.4. In TRM138R instruments
transistor optocouples
of npntype
are used as OUs. These optocouples’ outlets
have galvanic insulation from the
instrument’s circuit and are led out to the
exterior junction terminals. Transistor
optocouples are used, as a rule, to control
lowvoltage solidstate or electromagnetic
relay assemblies commuting power circuits
of electric load.
ATTENTION!
When optocouples are
used to control an electromagnetic relay
assembly, the latter’s winding shall be
connected in parallel with a semiconductor
diode whose parameters are selected at
Section 3
Instrument Design and Operation
Figure 8. LU operation with the preset
holding time
Figure 9. DAC output characteristics
Figure 10. Relays’ contacts connected in
parallel at operation under inductive loads
Содержание TPM138
Страница 23: ...22 TRM138 Setting up Procedures Section 6 Figure 16 Programmed parameters setting diagram...
Страница 24: ...23 TRM138 Section 6 Setting up Procedures...
Страница 30: ...29 TRM138 Appendix 1 Dimensional drawing...
Страница 31: ...30 TRM138 Instrument connection Appendix 2 Figure A2 1 Instrument terminal block contacts arrangement diagram...
Страница 35: ...34 TRM138 Figure A2 10 Example of connection of various type transducers Instrument connection Appendix 2...
