Utilities DCS extended in Sandwich

Pfizer's Sandwich site uses Omniflex distributed controllers to provide extensions to its utilities DCS within budget.

Pfizer's Sandwich site uses Omniflex distributed controllers to provide extensions to its utilities DCS within budget.

Using the Maxiflex distributed process automation controllers from Omniflex, Pfizer has extended its utilities DCS to handle smaller projects.

Pfizer is the UK subsidiary of the international pharmaceutical company of the same name.

Every month, more than two million patients in the UK are prescribed a Pfizer medicine.

Pfizer in Sandwich uses the MaxDNA DCS to control and monitor all of its utilities operations (about 6000 I/Os).

It has been upgraded many times and has given 16 years of trouble free service.

The only drawback was the cost of the hardware which was prohibitive on some of the smaller projects that Pfizer wanted to do.

Pfizer needed a system that would interface with the MaxDNA but at a reduced cost.

Pfizer chose the Maxiflex system, which uses the Isagraf IEC61131 programming language, the same as the MaxDNA, and has a built-in serial interface compatible with the MaxDNA.

Using the Conet industrial LAN, Pfizer extended its distributed control network to areas not previously viable.

Conet allows industrial strength communications on existing plant wiring up to 10km in a peer-to-peer configuration.

Capabilities for report by exception, dual redundancy and multiple network segments to suit the plant topology are features of the Conet network, which can support up to 126 nodes per segment and be connected with radio, PSTN and GSM networks to extend the communications infrastructure.

A Maxiflex node was installed as a gateway to the MaxDNA via a Modbus connection on RS485.

A Conet highway was then established between the gateway and eight Maxiflex P3 nodes around the plant running on existing plant cabling.

These nodes control and monitor some of the plant's smaller projects.

The information is then transferred to the MaxDNA via the Maxiflex gateway link.

"The system has been running for about ten months now with 100% reliability," said Tony Perry, Pfizer's Senior Engineer responsible for utilities.

Back to top