Scale Indicators: How to Choose a Weight Indicator

Updated November 12, 2026

The short answer: a scale indicator is the "head" of a scale: it powers the load cells, turns their signal into a weight and shows it, and sends that weight to a printer, PC or PLC. To choose one, match it to how many load cells your scale has, where it will be used (dry, washdown or hazardous area), what it needs to connect to, and whether the scale is legal-for-trade. A basic floor scale indicator costs a few hundred dollars; programmable controllers for batching and truck scales cost a few thousand.

What a scale indicator does

Load cells only produce a small millivolt signal. The indicator supplies the excitation voltage, reads the signal, filters out vibration, and displays a stable weight. Depending on the model it also handles zero and tare, counting, checkweighing, accumulation, truck in/out tickets, setpoints for filling and batching, and data output. Replacing a failed indicator is one of the most common scale repairs, and upgrading one is the cheapest way to add printing or connectivity to a scale you already own.

How to choose a scale indicator: 7 checks

1. Load cell inputs

Check how many load cells the indicator can power and at what impedance. Most floor scales use four 350 Ω cells, and many basic indicators are built for exactly that. Truck scales and large tank systems need an indicator that can drive more cells, or a multi-channel model for axle scales and weigh pads.

2. Display

LED displays are bright and easy to read from a forklift. Backlit LCDs are easier on batteries and readable in sunlight. For reading the weight across a warehouse or from a truck cab, add a remote display or scoreboard.

3. Housing and environment

ABS plastic and painted steel suit dry indoor use. Stainless steel suits washdown, food and wet areas. Hazardous locations need an intrinsically safe or explosion-proof indicator, specified to the area's classification.

4. Power

AC power suits fixed scales. A rechargeable battery suits portable floor scales, pallet jack scales and axle pads.

5. Outputs and connectivity

Common options are RS-232 serial for printers and PCs, USB, Ethernet, analog outputs, fieldbus cards for PLCs, and wireless. List what you need to connect to now and in the next few years.

6. Printing

If you need tickets or labels, choose an indicator with a built-in printer or one that supports your ticket printer.

7. Legal-for-trade

If you sell by weight or issue freight or truck tickets, the indicator, the load cells and the scale must meet your state's legal-for-trade rules, based on NIST Handbook 44. NTEP-approved models are available; ask us to confirm the certificate for the exact model before you buy, and see our NTEP and legal-for-trade guide.

Scale indicator models and prices

Prices are from SellEton product pages at the time of writing (November 2026). Check each product page for the current price.

See the full range in scale indicators and Rice Lake indicators and controllers.

Which features matter for your job

• Shipping and receiving: a clear display, tare, and a serial or USB port for a shipping PC or ticket printer. Accumulation helps when you weigh a shipment in several lifts.
• Parts counting and kitting: a counting mode with sample entry, and a model that stores piece weights for repeat parts.
• Checkweighing and packing: over/under limits with colored lights or a tolerance bar so operators can work without reading numbers.
• Truck and vehicle weighing: inbound/outbound weighing with stored tares, ticket printing, and support for the number of load cells in the deck. Pair it with a remote display so drivers can see the weight.
• Tanks, hoppers and batching: setpoints and outputs to run valves, gates and conveyors, plus a fieldbus or Ethernet link to the plant PLC. This is where programmable controllers earn their price.
• Portable and pallet jack scales: a rechargeable battery, a sleep or auto-off mode, and a rugged housing.

Buying only the functions you'll use keeps the cost down. A basic indicator does weighing, tare and counting well; you only need a programmable controller when the scale has to run part of a process.

Replacing an indicator on an existing scale

Most indicators work with most analog load cell scales, as long as the cell count and impedance are within the indicator's limits. Note the old indicator's wiring before you disconnect it, and expect to recalibrate the scale with test weights after the swap. Our load cell wiring guide covers the color codes. A new indicator on a legal-for-trade scale has to be set up and sealed by a qualified scale technician, and your state weights and measures office may need to be notified.

Scale indicator FAQs

Can I use any indicator with my floor scale?

Usually, if the scale uses analog load cells and the indicator supports the number and impedance of the cells. Digital load cell systems need an indicator made for that system.

What is the difference between an indicator and a controller?

An indicator shows and outputs weight. A controller adds setpoints and programming to run a process, such as opening a fill valve or stopping a conveyor at a target weight.

Do I need an NTEP indicator?

Only if the scale is used for legal-for-trade, such as selling by weight or issuing shipping tickets. For in-house process weighing, an NTEP model isn't required.

Can an indicator connect to my computer or PLC?

Yes. Serial and USB outputs connect to PCs and software, and Ethernet or fieldbus options connect to PLCs. Our weighing system integration guide explains the options.

Get help choosing

Tell us the scale type, number of load cells, environment and what the indicator needs to connect to, and we'll recommend a match. Call SellEton Scales at (844) 735-5386 or send us a message. For wireless data collection, see our Tuffbook Mini indicator post.