MEC 20 MICROPROCESSOR ENGINE/GENERATOR CONTROLLER
PM047 Rev 13 05/03/30
28
Thomson Technology
alarm and/or shutdown signal as programmed by the user. The engine oil
pressure analog input provides the following control function:
4.4.5.1.
LOW OIL PRESSURE #1 ALARM
The low oil pressure alarm fault circuit is activated when the oil pressure
drops below a pre-determined setpoint for a specified time delay. The low
oil pressure alarm fault is programmable for pressure setpoint level,
transient time delay settings and other functions. Refer to the
programming instructions for further information.
4.4.5.2.
LOW OIL PRESSURE #2 SHUTDOWN
The low oil pressure shutdown fault circuit is activated when the oil
pressure drops below a pre-determined setpoint for a specified time
delay. The low oil pressure shutdown fault is programmable for pressure
setpoint level, transient time delay settings and other functions. Refer to
the programming instructions for further information.
Note:
Low Oil Pressure shutdown may alternately be programmed and
wired as a digital fault input contact. Refer to
Section 4.3
for further
details.
4.4.6. ENGINE SPEED ANALOG INPUT
The MEC 20’s engine speed sensor measures AC voltage and frequency from
an engine mounted magnetic pick-up. The engine speed sensor provides
information to perform the following control functions:
Overspeed shutdown
Crank Disconnect control
Loss of speed signal detection
Starter Re-engage control
RPM display
Refer to the programming instructions for further information.
5.
CONTROL OUTPUT CONTACT DESCRIPTIONS
All output contacts from the MEC 20 Engine Controller are non-powered (i.e. dry contacts) and
are rated 10A/240Vac, 8A/24Vdc resistive (3A inductive, 0.4pf). Output contacts are not fused
therefore external overcurrent protection (maximum 10A) is required for all control circuits using
these contacts. Contacts indicated on schematic drawings and connection diagrams are shown
in a de-energized state and will change state upon activation of the specific control function.
