Deutz EMS2, System Description

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EMS 2
System functions
4.2.2 Override-Funktion
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In safety-critical cases , emergency engine shut-off or output reduction can be suppressed with the
limp-home button /diagnostic button (override signal). The EMS 2 is programmed in such a manner that
the overwriting of these engine protection functions applies only for a specific period of time (limp-home
time) or until the engine is shut-off.
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Depression of the button is confirmed via slow slashing (frequency approx. 0.5 Hz). The limp-home
time (override time) begins again each time the button is depressed. Excessively frequent actuation of
the button may damage the engine and lead to the expiry of the warranty (responsibility of the user).
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Override procedures are stored in the control unit.
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Following the expiry of the override time, the warning, reduction in power or the shut-off function are
reactivated insofar as the relevant conditions for this are still present.
4.2.3 Speed monitoring
Speed monitoring prevents engine damage as a result of excessive speed, and is defined prior to delivery
depending on the combination (e.g. EMS with MVS) and model series. The speed signal can be supplied to
the EMS 2 control unit in three ways:
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With a pick-up (magnetic speed sensor).
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Via the W terminal of the alternator.
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With data exchange via the CAN interface.
4.2.4 Temperature monitoring
Depending on the engine model series, temperature sensors are available for engine oil, coolant, cylinder
head 1 and 2, and reserve temperatures. Connection to the EMS 2 is carried out in two ways:
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Either via the inputs (see Chapter 5.1).
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Or via the CAN interface from other systems (MVS, EMR).
In addition, each time the temperature is exceeded, an output for initialising a lamp or a relay may be allo-
cated, see Chapter entitled Outputs 5.2.
If the temperature falls below the recovery threshold, the diagnostic lamp is shut-off, and the power reduc-
tion or emergency shut-off engine protection functions are reset.
4.2.5 Engine oil pressure and reserve pressure monitoring
Oil pressure monitoring is activated following the expiry of a fixed period of time after the engine has been
started.
Depending on the application, the connection to the EMS 2 can be carried out in two ways:
●
Via the inputs (see Chapter 5.1).
●
Or via the CAN interface from other systems (MVS, EMR).
In addition, each time the temperature is exceeded, an output for initialising a lamp or a relay may be allo-
cated, see Chapter entitled Outputs 5.2.
The warning limit is speed-dependent. In order to take pressure fluctuations into consideration, the oil pres-
sure may fall below the warning limit for a speed-dependent period of time before the engine protection
functions respond.
Following the expiry of the waiting period , the diagnostic lamp is continuously illuminated, insofar as the
signal still lies in the warning range.
If the oil pressure exceeds the recovery threshold, the diagnostic lamp is shut-off, and the power reduction
or emergency shut-off engine protection functions are reset.
Other pressures may be monitored depending on the application and the input assignment of the control
unit.