News

MEI #2 - Are All Bill Acceptors Alike? - A Technology Review

April 8, 2002

The answer is a resounding "NO." In fact, like a car, it's what's under the hood that most affects a bill acceptor's performance. Let's explore the inner workings - the technology, design, and mechanics - of a bill acceptor and how it affects acceptance rate, jam rate, security, and other bill-acceptor issues important to your customers.

Validation: optical vs. magnetic

Complex optical technology, pioneered by MEI (Mars Electronics International) in 1972, is currently the industry's most effective method to simultaneously achieve low jam and high acceptance rates, while maintaining tight security. Many bill acceptors in the U.S. currently validate bills using magnetic sensing combined with simple optical technology. By today's standards, this combination is a dinosaur - averaging a bill jam every 5,000 to 20,000 uses.

Here's why:

Unlike magnetic technology, which only detects the presence of magnetic ink in authentic bills, complex optical technology measures the various properties of that ink. Specifically, multi-wavelength optical sensors recognize a wide spectrum of light to more precisely identify and validate bills - making acceptance of authentic bills very high. Complex optical technology can even recognize bills of different quality and fitness for high acceptance of worn, "street" money. But, the key is this: complex optical technology does not indiscriminately accept all bills.

Because it is more precise, complex optical technology excels at detecting counterfeit bills to prevent fraud. This is important as today's thieves are getting harder and harder to outwit.

Also, consider the jam-rate improvement of complex optical technology over simple magnetic: optical has a jam rate that's about 3 to 4 times better (on average) than magnetic technology. Magnetic heads require pinch rollers that lightly pinch the bill as it enters the cavity, dramatically increasing the chances of the bill being pulled, ripped, or otherwise jamming the bill acceptor. Optical systems, however, beam frequencies of light through the bill without ever physically touching it. The result is dramatically fewer jams.

To flash or not to flash

In the past, U.S. bill series remained active for as long as 20-30 years. However, modern reproduction technology allows minor -often-imperceptible - security enhancements to be made every few years. Your customers need an easy, cost-effective way to update their bill acceptors so they recognize new bills' unique, updated properties. To provide your customers with this added value, specify bill acceptors with built-in, re-programmable flash memory. Flash allows fast, hassle-free programming through the interface to accept and validate new bills - no complicated chip swap needed. And this feature goes beyond cash to allow for programming of software upgrades and recognition of unique coupons or special retail cards.

Security: strike the right balance

Without security mechanisms in place, bill acceptors will simply accept all bills - including forged currency. It's a trade-off. Retail kiosks must be built with bill acceptors that balance acceptance with security to satisfy both the end-user's desire to have bills accepted and the kiosk owner's need to prevent acceptance of forged bills.

To add value to your kiosks, consider integrating multi-mode security bill acceptors. Your customers will be afforded the flexibility of choosing what level of security they need for their particular location and application. Some of the most advanced bill acceptors can even be programmed - manually or electronically - to set different security modes for different times of the day. For example, a kiosk retailer might want higher customer-friendly bill acceptance during the day and increased security at night when crime occurs more frequently.

Maintain high acceptance and reduce jams with self-calibration

Experience has shown that jams occur more frequently when a bill is rejected. Therefore, a high acceptance rate reduces the opportunities for jams to occur. Inevitably, dirt, dust, and other debris will rub off bills and accumulate in the bill-acceptor cavity, reducing acceptance. To minimize maintenance and the associated downtime, specify a bill acceptor with self-calibration technology, which allows the bill acceptor to automatically compensate for dirt in the cavity of the bill path by increasing the strength of the optical light. The increased light intensity ensures that the bill acceptor maintains its acceptance rate and that the bill continues its transport along the bill path. This dynamic feature complements complex optical technology and typically allows for thousands of bill insertions before any service or maintenance is necessary.

Give bills a smooth ride

It's important that a bill acceptor be capable of transporting a wide range of bills smoothly from the bezel to the cassette. Once the bill acceptor has read the bill, it must be transported to the proper place - either back out to the customer if rejected, or into the cash box if validated. To ensure this all happens properly and conveys bills in any condition (tattered, dirty, folded), specify a high-quality transport mechanism with a short bill path and no mechanical interference.

Lastly, safeguard your products by partnering with a vendor that provides a comprehensive warranty, national service coverage, and on-site technical support. A bill acceptor designed with reliable, high-quality components and durable mechanics to perform in an unattended environment will keep downtime to a minimum. But, remember, we're talking about a very complex blend of hardware, software, and interfaces that need to be integrated into another intricate host - the kiosk. Make sure your bill acceptor vendor is willing to work with you to optimize the performance of your kiosk design.