This section is available on request - MAN Diesel & Turbo

MAN B&W 16.02
Safe condition/
purged system
Start of auxiliary
equipment
Purging
Safe condition
If the failure relates to the purging system it may
be necessary to carry out purging manually before
an engine repair <strong>is</strong> carried out. (<strong>Th<strong>is</strong></strong> will be
explained later).
The Dual Fuel Control system <strong>is</strong> a single system
without manual back�up control.
However, the following equipment <strong>is</strong> made redundant
to secure that a single fault will not cause
fuel gas stop:
• The communication network <strong>is</strong> doubled in order
to minimize the r<strong>is</strong>k of interrupting the communication
between the control units.
• Vital sensors are doubled and one set of these
sensors <strong>is</strong> connected to the Plant Control and
the other to the Safety System. Consequently
a sensor failure which <strong>is</strong> not detectable <strong>is</strong> of no
consequence for safe fuel gas operation.
Control Unit Hardware
Start of fuel
gas supply
Stop to safe
condition
Fig. 16.02.02: Fuel gas operation state model
Running on
fuel gas
178 53 70�4.0
For the Dual Fuel Control System two different
types of hardware are used: the Multi Purpose
Controller Units and the GCSU, both developed
by MAN B&W Diesel A/S.
The Multi Purpose Controller Units are used for
the following units: GECU, GACU, GCCU, and the
GSSU. In the following a functionality description
for each units <strong>is</strong> given, see also Fig. 16.02.01.
Gas Main Operating Panel (GMOP)
Page 3 of 4
For the GI control system an extra panel called
GMOP <strong>is</strong> introduced. From here all manually operations
can be initiated. For example the change
between the different running modes can be done
and the operator has the possibility to manually
initiate the purging of the gas pipes system with
inert gas.
Additionally it contains the facilities to manually
start up or to stop on fuel gas.
GECU, Plants control
The GECU handles the Plant Control and in combination
with GCCU it also handles Fuel Control.
Example: When ‘dual fuel’ Start <strong>is</strong> initiated manually
by the operator, the Plant Control will start
the automatic start sequence which will initiate
start�up of the sealing oil pump. When the
engine condition for Dual Fuel running, which <strong>is</strong>
monitored by the GECU, <strong>is</strong> confirmed to meet the
prescribed demands, the Plant Control releases
a ‘Start Dual Fuel Operation’ signal for the GCCU
(Fuel Control).
In combination with the GCCU, the GECU will effect
the fuel gas injection if all conditions for Dual
Fuel running are fulfilled.
The Plant Control monitors the condition of the
following:
• HC ‘Sensors’
• Gas Supply System
• Sealing Oil System
• Pipe Ventilation
• Inert Gas System
• Network connection to other units of the Dual
Fuel System
and, if a failure occur, the Plant Control will automatically
interrupt fuel gas start operation and
return the plant to Gas Safe Condition.
The GECU also contains the Fuel Control which
includes all facilities required for calculating the
fuel gas index and the Pilot Oil index based on the
command from the conventional governor and the
actual active mode.
MAN B&W ME/ME-C/ME-B/-GI engines 198 50 61-9.1
MAN Diesel