Battery Application Solutions for Packaging Lines: Ending Voltage-Dip Downtime

Packaging plants lose more product to brief power quality events than to outright blackouts. A voltage dip lasting two seconds can trip a servo drive, tear a film web, or scramble a date coder, and the line then needs minutes of cleaning and re-threading before saleable output resumes. Purpose-built battery application solutions address this at three levels: ride-through for sensitive drives, backup for controls and coding, and peak shaving against demand charges.

Where the Money Actually Goes

The cost of a dip is not the electricity, it is the waste. A form-fill-seal machine running at 120 packs per minute scraps 200 units in a two-second event, plus film, product and the labour to clear the fault. Add the lost output while the line restarts and a single event can exceed the annual maintenance budget of the battery system that would have prevented it. Plants that log dip events for a month almost always find a stronger business case than they expected.

Three System Architectures

The first is centralised: one large UPS or battery energy storage unit feeding the whole line’s control and drive bus. The second is distributed, with small DC units protecting individual servo drives and PLC racks, which is cheaper to retrofit but harder to monitor. The third is a hybrid, where a central bank covers the general bus and dedicated units protect the few assets that cannot tolerate even a momentary transfer.

Peak Shaving as a Second Revenue Line

Once a battery is installed for ride-through, its idle capacity can shave demand peaks. Packaging lines draw sharp spikes when several machines start together, and utilities bill the highest 15-minute demand in the month. Discharging the bank through those peaks lowers the demand charge, which in many tariffs repays 20–40% of the system cost without touching production.

Packaging Line Backup Options

Integration With Existing Drives

Modern servo drives have a DC link that accepts external DC support, which is often the cheapest ride-through route because it bypasses the inverter entirely. For older AC drives, a central UPS on the supply side works but must be sized for the inrush of simultaneous restarts. Either way, tie the battery BMS into the plant SCADA so state-of-charge, cell temperatures and event logs appear alongside line OEE.

What to Ask a Supplier

Ask for a dip study before a quotation, since protection without measurement is guesswork. Require the transfer time in milliseconds, the specified autonomy at your real load, and confirmation that the unit supports your drive topology. Finally, get the peak-shaving control logic in writing: some systems can ride through dips but cannot do demand-charge work.

People Also Ask

How long must backup last on a packaging line? Most damage comes from events under three seconds, so 30–60 seconds of ride-through prevents the majority of scrap. Longer autonomy only pays if you also need orderly shutdown.

Is a flywheel better than a battery? Flywheels excel at very frequent, very short events and long life with little maintenance. Batteries win where you also want minutes of autonomy or peak shaving.

Can one battery protect several lines? Yes, if they share a bus and the bank is sized for simultaneous restart inrush. Separate protection is simpler when lines run independently.

Does peak shaving interfere with backup? Not if the controller reserves capacity. Specify a reserve floor, typically 30–50%, that demand-charge work can never consume.

Written by Karl at China Battery Technology. Request a quote.