AUTOMATIC CONTROL PANEL FOR
EMERGENCY GENERATORS SET

TYPE AT 30

The Electric Control panel, combined with an emergency Generator Set, allows the realization of a system able to supply electric power within a few seconds of Utility Mains failure. The enclosure is of steel sheet, accurately machined and subject to a painting treatment using high resistance epoxy powder. All electronic circuits for monitoring, control and signalling are included in one single, compact microprocessor control card, flush mounted on the Panel front door.
 

OPERATION

By means of key operated selector switch, the following modes can be selected:

OFF/LOCKED: any operation excluded; engine start inhibition, with forced control of load supply from the mains.
MANUAL: engine manual start and stop controls are enabled. The Gen Set protection devices are activated. The starting control is automatically disabled when the engine is running.
AUTOMATIC: automatic start upon mains failure, even on one single phase, for min./max. voltage, or upon external consent. Starting is obtained through a cycle of starting attempts, each followed by a pause. In case of starting failure, the control panel gives an optical signal and forces the Gen Set to shutdown, thus avoiding battery discharge. Upon engine starting, the starter motor is automatically disconnected by an electronic control device. Once the rated conditions are reached, the Gen Set is connected to the load. The Gen Set is automatically controlled by an appropriate protection device. When the mains returns within the normal limits, the Gen Set is automatically disconnected from the load. The load is then supplied by the mains and the engine is stopped after an adjustable cooling time.
It is permited to TEST the automatic start for periodical testing operations with safety protections enabled. Mains / Gen Set changeover is disabled. Upon mains failure, the load is immediately supplied by the Gen Set.

AUXILIARY SERVICES
The control panel includes:

• Elettronic Automatic Battey Charger fed by the Load Line
• Single-phase voltage supply for engine preheating
• Acoustic alarm
• Dedicated voltage-free contact (connected to an internal board) for generating set failure
• Programmable periodic automatic test, as period and time required of the test itself
• Motor driven-pump conrol circuit for the automatic decanting from the external tank (optional)

CONTROLS

• Engine start push-button
• Engine stop push-button
• Acoustic alarm silencing and programming and reading display selection push button
• Manual control for changeover switch
• Emergency stop push-button
• Reset push-button

DIGITAL MEASURING DEVICES
The Control Panel includes the following digital instruments:

• Generator voltmeter: Phases L1/L2 L2/L3 L3/L1
• Mains voltmeter: Phases L1/L2 L2/L3 L3/L1
• Generator ammeter: Phases L1 L2 L3
• Generator frequency meter
• Gen Set hours counter
• Battery voltmeter
• Start-counter

OPTIONALS

• Oil Pressure Gauge
• Water thermometer
• Revolution counter
• Fuel level gauge

OPTICAL SIGNALLING AND GEN SET PROTECTION
A set of light emitting diodes are used for signalling the current status of the Generator Set and for the visualization of alarm intervention.

STATUS

• Mains live
• Generator live
• Mains contactor closed
• Generator contactor closed
• Engine running

ALARMS WITHOUT SHUT-DOWN

• Fuel reserve
• Maximum fuel level (for automatic topping up systems from an external tank)
• Battery failure

OPTIONALS

• Pre-alarm for low oil pressure
• Pre-alarm for high engine temperature
• Pre-alarm for low radiator water level

ALARMS VISUALIZED ON DISPLAY

• Over load
• Generator under-voltage
• Generator over-voltage
• Generator under-frequency
• Generator over-frequency

Other alarms are available (without shut-down).

ALARMS WITH ENGINE SHUT-DOWN

• Engine over crank
• High engine temperature
• Low oil pressure
• Engine over speed
• Generator overload
• Fuel end
• Low radiator water level (for water cooling engine)
• Emergency stop

An acoustic alarm is used for signalling in case of defect. Signalling persists, even if the defect is cancelled, until it is released (through RESET).

LIST OF THE MAIN SETTABLE PARAMETERS
The control card allows to set all the operating parameters. Each parameter corresponds to a code number which identifies it and allows its value to be set.
The main parameters are:

• Mimimum mains 3-phases voltage
• Threshold for generator voltage recognition
• Gen Set connection delay
• Mains return delay
• Time delay for supply from Gen Set
• Engine cooling delay
• Start pulse duration
• Shut-down pulse duration
• Number of starting attempts
• Generator under frequency threshold
• Generator over frequency threshold
• Generator under voltage threshold
• Generator over voltage threshold
• Generator periodical test start period
• Generator periodical test duration
• Over speed threshold
• Changeover switching delay
• Low oil pressure
• Maximum mains voltage
• Pause time between 2 starting trials
• Frequency recognition starting engine
• Current transformer ratio

Other parameters are available to personalize the device, in relation to the various applications.

INTERFACE WITH TELECONTROL SYSTEM (OPTIONAL)
The microprocessor control card is equipped with RS 232C for possible connection to a local PC.

TECHNICAL FEATURES

• Supply voltage: 230 / 400 Vac (other to be specified)
• Auxiliary voltage: 12 Vdc or 24 Vdc
• Frequency: 50 Hz or 60 Hz
• Insulation: > 50 Mohm
• Dielectric strength AC: 2500V/1'
• Dielectric strength DC: 1000V/1'
• Level of protection: IP 40 (other protection levels as optional)
• Colour: RAL 7032
• Ambient temperature min./max.:  -10 / +60° C
• Conforming to: CEI - IEC - EN

POWER CIRCUIT
The power circuit, when included, is separated from the auxiliary control circuits, as per current safety regulations. In standard configuration, with front door open, the level of mechanical protection is equivalent to IP20.
Standard configuration includes:

• 4 poles Mains/Gen Set changeover
• 4 poles automatic circuit breaker
• Differential device protection (optional).

When Mains/Gen Set changeover is external to the control panel, dedicated voltage free contacts for changeover control (connected to an internal terminal board) are supplied.