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Power Monitoring with MW100 and PR300

Industry: Automobile Manufacturing

Product: Network Solutions

MW100

PR300

Introduction

A large OEM parts supplier to the automotive industry

has been a Yokogawa customer for several years. In

the past, Yokogawa sold the customer field

instruments and data logging equipment for measuring

and recording environmental conditions within their

facility. A new application surfaced; the customer

wants to measure and quantify the electrical energy

consumption and other utility costs for each assembly

line so they can accurately assign these costs to each

component. Yokogawa was called in to assist with the

project.

Application

The customer has over one hundred assembly lines or

work cells targeted for energy monitoring. The plant

provides pressurized air and nitrogen as well as

electricity to operate each work cell. In order to

determine the true cost to manufacture each

component the amount of air, nitrogen and electricity

needs to be displayed, totalized and logged. Historical

consumption data saved by the PC data logging

software will run through calculations using energy

cost rate information to determine the energy cost for

the assembly line over a specific time period. The

customer also wants a low cost method for line

managers to have real-time access to the process

data. The new system must be network-enabled and

easy for the instrument and control technicians to

configure and maintain.

Solution

An integrated system was proposed using an MW100

for data logging, two PR300 power meters for the

electrical measurements and a Yokogawa flow meter

and differential pressure transmitter for the air and

nitrogen measurements. A custom enclosure with a 24

VDC power supply for the field instruments, circuit

breakers and terminal blocks would house the MW100

and power meters.

A local Yokogawa systems integrator designed and

built the enclosure containing the instrument package.

The project sales engineer configured the MW100 for

MODBUS data communications with the PR300s and

the flow rate measurements. Nitrogen and airflow are

measured in Standard Cubic Feet per Minute then

totalized and grouped in math channels. The math

groups are reset at midnight daily so a consumption

total is provided each day.

The PR300s measure a mix of single and three phase

electrical loads on five separate panels. Each PR300

provides panel voltage, current and kWh consumption

values to the MW100 using serial MODBUS RTU

communications. This data is read by the MW100 and

placed in math channels. All data is archived by the

MW100 to the CompactFlash

card. DAQLOGGER

software with Gate MX/MW (required when used with

MW100) gathers all MW100 real-time channel data

(including PR300 data on math channels) via an

Ethernet network connection.

Any PC in the plant will allow the managers to view

MW100’s real-time data and alarm events via Internet

Explorer – a great convenience and cost-saving

feature since no additional software is needed.