Clayton Thermal Products UK

Steam Generators and Exhaust Gas Boilers 150 - 40,000 kg/h

PLC MASTER SEQUENCE CONTROL PANELS

Copyright © 2007

CLAYTON PLC MASTER SEQUENCE CONTROL PANELS

are easy to operate and provide flexible, sophisticated control and sequencing of two or more plc controlled steam generators. They work in conjunction with the individual control panels fitted to each Clayton Steam Generator assembly. The control is designed to harness the rapid start-up and response capabilities of Clayton Steam Generators to give process advantages to the user.

GENERAL DESCRIPTION
The Sequence Panel has only a small number of operator switches and a front mounted plc display. The display unit has two lines of 20 characters as well as keys for selecting operating conditions and adjusting parameters. The settings are password protected. Connection between the sequence panel and the generator panels is by means of modbus serial communication modules. Modbus communication can also be included in the sequence panel for client use.

A time clock is incorporated into the display unit which can be set to start and stop steam generation at different times each day.

SEQUENCING

A pre-determined sequence of generator operation is automatically performed based on steam demand, signalled by pressure fluctuations in the steam main.

Various sequences can be set on a manually adjusted generator priority by a menu system on the plc display. This means that, for example - when one generator is at a particular firing rate for longer than a set time the other generator can be arranged to come in when additional steam is required and the load can be shared - and so on.

Switching on steam generation from the sequence panel will therefore automatically run the entire system.

INCOMING POWER SUPPLIES

Three-phase power can be fed into the sequencing panel for distribution - or into each individual panel. Motor starters are provided in the panels and other supplies are derived from the main supply.

ADDITIONAL FUNCTIONS

Shut-down - Actuation of the emergency stop on the sequence panel will shut down all steam generators.

Hotwell Level Control – The hotwell water level is controlled from the sequence panel and a three-way switch on the panel front allows selection of automatic hotwell fill, manual fill or off.

Chemical Pump Control – Control of hotwell chemical dosing takes place from the sequence panel. A three way switch is also provided for the chemical pump to permit selection of Automatic / Manual / or off.

Hotwell Heating – Where hotwell heating is regulated by means of a steam valve this is controlled from the sequence panel.

Blowdown – On systems with automatic blowdown the sequence panel will send signals to operate the automatic blowdown as required.

Alarm - A common alarm signal is provided.


	Steam Generators and Exhaust Gas Boilers 150 - 40,000 kg/h
	PLC MASTER SEQUENCE CONTROL PANELS	Copyright © 2007
CLAYTON PLC MASTER SEQUENCE CONTROL PANELS are easy to operate and provide flexible, sophisticated control and sequencing of two or more plc controlled steam generators. They work in conjunction with the individual control panels fitted to each Clayton Steam Generator assembly. The control is designed to harness the rapid start-up and response capabilities of Clayton Steam Generators to give process advantages to the user. GENERAL DESCRIPTION The Sequence Panel has only a small number of operator switches and a front mounted plc display. The display unit has two lines of 20 characters as well as keys for selecting operating conditions and adjusting parameters. The settings are password protected. Connection between the sequence panel and the generator panels is by means of modbus serial communication modules. Modbus communication can also be included in the sequence panel for client use. A time clock is incorporated into the display unit which can be set to start and stop steam generation at different times each day. SEQUENCING A pre-determined sequence of generator operation is automatically performed based on steam demand, signalled by pressure fluctuations in the steam main. Various sequences can be set on a manually adjusted generator priority by a menu system on the plc display. This means that, for example - when one generator is at a particular firing rate for longer than a set time the other generator can be arranged to come in when additional steam is required and the load can be shared - and so on. Switching on steam generation from the sequence panel will therefore automatically run the entire system. INCOMING POWER SUPPLIES Three-phase power can be fed into the sequencing panel for distribution - or into each individual panel. Motor starters are provided in the panels and other supplies are derived from the main supply. ADDITIONAL FUNCTIONS Shut-down - Actuation of the emergency stop on the sequence panel will shut down all steam generators. Hotwell Level Control – The hotwell water level is controlled from the sequence panel and a three-way switch on the panel front allows selection of automatic hotwell fill, manual fill or off. Chemical Pump Control – Control of hotwell chemical dosing takes place from the sequence panel. A three way switch is also provided for the chemical pump to permit selection of Automatic / Manual / or off. Hotwell Heating – Where hotwell heating is regulated by means of a steam valve this is controlled from the sequence panel. Blowdown – On systems with automatic blowdown the sequence panel will send signals to operate the automatic blowdown as required. Alarm - A common alarm signal is provided.