P/T4 Pressure & Temperature AC Fan Control System - Automatic or Manual Modes

The P/T4 Series Ventilation Control System is a state-of-the-art digital ventilation control system that is designed and manufactured by Delta T Systems specifically for the rigors of the marine engine room.
The P/T version monitors both air pressure and temperature.

With thousands of these systems in use, over the years Delta T has been able to incorporate customer requests for features and modifications into the design of this fourth generation of the P/T4 producing the most reliable and robust offshore fan control system of its type in the world.

The P/T4 may be run in automatic or manual mode.
Normal operation for this system is in automatic mode, which is activated as soon as the vessel’s engines are started. In Automatic mode, engine room temperature and combustion air intake are automatically controlled to optimum levels based on temperature and pressure.

The system includes a color touch screen Fan Control Interface (FCI) with the ability to attach up to ten (10) remote displays. Also included is an integrated alarm output that can be connected to a vessel's central alarm system.
Help screens and simplified parameter and monitoring screens make operation and adjustment fast and easy.


Heavy on the technical side...
The P/T4 System allows the variable speed control of two or more three-phase fans via a digital touch screen Fan Control Interface (FCI). Each system may be configured to accept single or three phase AC input power to the ASDs (Adjustable Speed Drives), depending on the available power aboard the vessel.
The ASDs allow the fan motors to be speed controlled with full reversing capability and virtually eliminates the high starting loads associated with typical single-phase fan installations.

Auto Mode — The P/T4 starts in Auto Mode when the engines are started. When the P/T4 system switches to Auto Mode, the exhaust fan(s) speed is adjusted automatically as the temperature increases, measured by a sensor located within the engine room.
The intake fan(s) speed is controlled by an engine room pressure sensor. This sensor requires a sensing tube to the outside atmosphere as well as to the engine room space to measure the differential pressure. As the engines demand greater volumes of air and the exhaust fan(s) flow increases as temperature rises, the intake fan(s) speed will increase to supply the required airflow, thus maintaining the correct pressure and volume under any conditions.

Quiet Run — Upon main engine shut down, the P/T4 ventilation control system switches to the Quiet Run Mode which cools the engine room down at a user specified fixed fan speed. Once a user specified temperature has been reached, the fans will stop thermostatically.

Manual Mode — In addition to the two automatic modes of operation there is a Manual Mode. The Manual Mode allows the operator to control the fan speed and direction independently for maintenance or unusual situations. This mode of operation is not recommended for use when underway and the main engines are running.