How to Maximize the Combinations of Your Multihead Weigher or Combination Scale

Written by Amanda King, Marketing Manager

In food packaging, multihead weighers, also known as combination scales, drop a pre-determined target weight of product into diverse types of packaging using multiple heads at a time. (Hence the name, multihead.) These heads are sometimes referred to as buckets. The scale uses the best available combination of buckets – usually 3 to 4 buckets at a time – to drop the most accurate weighment possible to achieve the desired target weight.

On a multihead weigher, the number of possible combinations to drop is determined by the number of weigh heads on the scale. The total number of possible combinations can be calculated using simple math: Ctotal = 2n where ‘n’ equals the number of weigh heads on the scale.

For example, on a 12-head scale, the total number of possible combinations is 212 (2x2x2x2x2x2x2x2x2x2x2x2) which equals 4,096 combinations. 13 available weigh heads on a scale means that 2 is raised to the thirteenth power, resulting in 8,192 combinations. A 14-head scale – 2 raised to the fourteenth power – has 16,384 combinations.

Note that for each additional weigh head added, the number of combinations double. Conversely, for each weigh head that becomes unavailable to use, the number of combinations cuts in half. This does not mean that you need to upgrade your existing or future scale with more heads though, but it does mean it is important to ensure all weigh heads remain functional during production.

To the naked eye, losing one lane on a scale may not look like a huge problem. Remember though, on a 14-head scale, there are 16,384 possible combinations. With 13 heads (213) that is cut in half and there are only 8,192 possible combinations. With fewer available combinations, your giveaway is going to increase.

Consider how much that may cost you:

For the sake of keeping the math simple, let’s say you package 1.25 ounces of pistachios into bags. You’re running this product on a 14-head scale at 100 bags per minute – 6,000 bags per hour. You average 1 gram of giveaway per bag. That’s 6,000 grams – 13 pounds – of giveaway per hour. Your cost is $10 per pound.

Now, let’s say you lose a weigh head. To maintain your production speed of 6,000 bags per hour, your average giveaway increases to 2 grams. How much is the additional giveaway costing you because you have a lane down?

This increase in giveaway results in an extra 13 pounds of product being given away per hour, costing you an extra $130 per hour. You’ve just doubled the cost of the product you’re giving away.

Running an 8-hour shift? That’s an extra $1,040 being given away. Running two shifts a day, Monday through Friday? That’s $2,080 per day, or $10,400 in additional giveaway per week in pistachios. You can figure out how much you lose over the course of a year.

All because just one weigh head on one scale was down.

The math does not lie. The money can add up. Fast. Especially when you’re weighing items that have a higher value by weight like pistachios or other nuts or an application like cannabis.

So, what do you do in order to reduce loss, save your business money, and operate as efficiently as possible. A weigh bucket on a scale can become unavailable for a variety of reasons. One of the most serious is due to a deformed load cell in an actuator causing the corresponding lane on the scale to become inhibited.

To ensure you are optimizing the performance of your scale – and your bottom line – Yamato Corporation recommends keeping at least one actuator in stock for each model of scale you own. The investment in having this vital scale component in stock at your facility will easily offset the money lost if a scale is not running properly for an extended period of time.

Yamato’s knowledgeable team of parts experts can help you get the genuine Yamato parts you need for your scale. Consider ordering a new actuator now – or add one to your next parts order. For more information, visit our parts and service page.

Whenever you’re replacing parts for your weigher, Yamato Corporation suggests you avoid using aftermarket parts. While the price may be enticing on these pieces, the negative impact these parts can have on your scale can be costly. Often, these aftermarket parts are not held to the same tolerances and quality standards as genuine Yamato parts. This includes those suppliers that claim to rebuild actuators to Yamato standards.

In addition to offering brand-new actuators for our scales, Yamato Corporation also offers refurbished genuine Yamato actuators. We have an actuator exchange program that allows you to get your scale back up and running, but at a reduced cost.

Our actuator exchange program operates out of our new Wisconsin HQ. We also have technicians rebuilding actuators in our West Coast facility. To take advantage of this program, the process is simple:

  1. Place an order for an actuator from our exchange program
  2. You are invoiced for the full price of a new actuator
  3. Return your damaged actuator to us and upon receipt of your damaged actuator, receive a 50% credit

One important thing to note is that these actuators are not just repaired – they are completely refurbished, making them good as new. Any technical issues are resolved and all related parts with general wear are replaced. These actuators are thoroughly tested before they are made available for sale, and all these actuators come with a warranty. If you order before 3:30pm Central time during the week, we can often overnight the actuator to you to help further minimize your scale’s downtime.

We offer this program because we know you need nonstop performance. We promise you will get that from our scales, and from us. That is what we like to call the Yamato Difference.

To order Yamato actuators or other genuine Yamato parts for your Yamato multihead weigher, don’t hesitate to contact us or send an email directly to parts@yamatocorp.com.