Control system for the rocking calmer "SKAT-1031"

The system is designed to control the steering devices of the ship's side rudders, maintain the specified amplitude (magnitude) and frequency (period) of the on-board pitching of a moving vessel by changing the angle of rotation of the rudder pen in the plane of the ship's midship frame.

The rocking calmer system provides operation in two modes:

-Rocking calming mode (when the ship's speed is up to 12 knots);

-Ship rocking mode (when the ship's speed is in the range from 5 to 10 knots).

On-board steerable rudders are located sideways from the outside of the vessel's hull and create a torque that counteracts the ship's side pitching or creates it, depending on the selected mode. The total number of SR is 2 pcs. (one per board).

Power supply network parameters

The system is powered by the ship's power supply (three-phase 400 V electrical network). Deviations from the nominal values of the supply network are shown in the table below:

Parameter	Deviation from nominal values, %		Duration of short-term deviation, s
Parameter	Long-term	Short-term	Duration of short-term deviation, s
AC voltage	+6 -10	+20 -30	1.5 1.5
Frequency	±5	±10	5

The power consumption for the system's own needs it does not exceed more than 2000 Watts (at a mains voltage of 400 V).

The degree of protection of the system equipment-IP44.
The communication of «SCAT-1031» with external control systems is provided by the following signals:

Analogue signals

Digital signals

Digital connection

Inputs

From 4 to 20 mA (resistance is not more than 200 Оm)

24V

«dry contact»

Modbus TCP/IP

Outputs

From 4 to 20 mA (the load is not more than 500 Оm)

24V «dry contact» (relay outputs no more than 0,5A)

The main parameters provided by the SKAT-1031

In terms of providing functionality:

ship rocking mode;
rocking calming mode;
uninterrupted communication with external ship systems

In terms of providing indication and EWS (emergency warning system):

protective shutdown devices;
control of the availability of power;
network voltage monitoring;
phase break control;
protection against short - circuit currents;
parameter control and protection of pump electric motors;
monitoring of parameters of hydraulic system sensors;
uninterruptible power supply CS from UPS;
registration of SR and CS malfunctions, recording in a non-volatile log of accidents and warnings;
issuance of fault alarms for SR and CS to local and remote control posts;
accident acknowledgment;
emergency stop.

In terms of providing control:

local control (from the buttons on the front panel of the PMS and the touchscreen of the LCD);
remote control of the equipment (from the touch screen of the control panel and external ship's control panels);
emergency stop from any control station;
priority of control from the local control post.

SC "Skat-1031" consists of the following parts:

- local control device (hereinafter referred to as LCD);

- control and alarm panels (hereinafter – CAP);

- pump motor starter (hereinafter – PMS);

- rotation angle sensor (hereinafter referred to as the RAS);

- tilt angle indicator (hereinafter – TAI);

- the distribution box (hereinafter – DB).

CAP