Watlow Eurotherm Cost efficiency for electric furnaces

The rise in power factor and peak demand charge

penalties is driving the need for better energy

efficiency in electric heat treatment furnaces. Installing

an EPower advanced thyristor power controller

with predictive load management offers a variety

of efficiency benefits, compared to legacy analog

thyristor and variable reactance transformer (VRT)

controlled designs.

Lower energy costs

Hybrid firing modes and predictive load

management strategies offer energy saving

efficiency improvements:

• Typical power factor (PF) better than 0.9 helps

to meet the PF limits set by utility suppliers,

reducing the risk of PF penalty charges

• Predictive load management can stabilize

power demand, helping to reduce peak

demand charge penalties

• Typical energy savings ≈10%

• Typical ROI < 2 years [1]

Reduce unplanned downtime

Improved power efficiency combined with

diagnostics and health condition monitoring, help

to improve overall system robustness:

• Less equipment to maintain – no need for

power filters, power factor correction devices

or extra water cooling systems

• Monitoring and notification of key parameters

provide simplified diagnostics of process fault

conditions, for faster maintenance

• Advanced notification of heater deterioration

enables pre-ordering and scheduling of

replacement parts

• Predictive load management can keep the

power demand within the capability of the

power line, helping to reduce the risk of

power outages

Improve furnace performance

High accuracy temperature measurement

and precision power control help to improve

workpiece throughput and quality:

• High quality heat treatment

• Repeatable performance throughout the

furnace temperature range

• Achieve higher Nadcap furnace class

temperature uniformity

CapEx savings

An EPower controller based power supply

solution often costs less than an analog thyristor

or VRT design:

• Expensive additional power factor correction

systems are not required. Transformers can

be air cooled, or water cooled using the

furnace cooling system

• Digital thyristor control allows space saving,

due to a typically smaller footprint than analog

designs

• Ethernet connectivity enables communication

with other instruments and platforms,

reducing wiring costs and allowing access to

key parameters

• Greenfield electrical distribution systems

can be a smaller size due to load sharing

and shedding, which balances and limits the

power demand on the supply