Comparing Load Cell Meter Filter Settings on Morehouse 4215 Load Cell Meters
A common question at Morehouse we are frequently asked involving our 4215-meter load cell meter is if there is a performance difference between using different filter settings.
We decided to take things further for this article by testing a standard 4215 indicator versus our newer 4215 Plus indicator. We then compared the filter settings of minimal filtering 1-1 with the slowest filtering setting of 2-4.
We hooked up each meter to a load cell simulator and captured roughly 22,000 data points at the 2 mV/V setting on the simulator.
Load Cell Meter Filter Settings
Load cells are transducers that convert force or weight into an electrical signal, and load cell meters interpret and display this signal.
The load cell meter filter settings are adjustments that affect the way the meter processes the incoming signal.
These filters are essential in minimizing noise and providing stable and accurate force readings.
The options for filter settings are often dependent on the manufacturer of the meter. These options range from no filter to some specialized filters.
In general, when we discuss the common filters, we are discussing these.
Low-Pass Filter: Allows low-frequency signals to pass through while attenuating higher frequencies.
High-Pass Filter: Allows high-frequency signals to pass through while attenuating lower frequencies.
Type I filters are suitable for removing most noise but may leave some jitter on the end digits.
Type I filters provide a linear phase response, preserving the timing relationships of different frequency components.
Type II are more advanced filters optimized for the typical industrial environment.
Type II filters have a non-linear phase response, allowing for potentially lower latency but introducing phase distortion.
There are also some specialized filters worth mentioning. Three of our favorites are the Gaussian, Butterworth, and Bessel filters.
A Gaussian filter, or a Gaussian blur, is commonly used in image and signal processing to reduce noise and smooth images or signals.
It applies a weighted average to each point in the signal, with the weights given by a Gaussian distribution.
This filter is characterized by its bell-shaped response and is often used for blurring and noise reduction.
A Butterworth filter provides a maximally flat frequency response in the passband and is commonly used in applications where a flat response is crucial.
It has a more gradual roll-off than Chebyshev filters, and while it introduces phase distortion, it is often preferred for applications where a consistent phase response is not critical.
Bessel filters are known for their nearly constant group delay, meaning that all passband frequencies experience similar delays.
This property is helpful in applications where maintaining the phase relationship between different frequencies is important, such as in audio signal processing.
The Morehouse HADI indicator has multiple filters in the advanced settings that can be changed.
The Morehouse 4215 filters are split into Type I and Type II.
Figure 1 Morehouse 4215 filter settings
Question: Is there a performance difference between using different load cell meter filter settings?
4215 Standard Load Cell Meter Filter Settings Comparison
We evaluated the load cell meter filters by choosing the most basic option of Type I, Level 1 (labeled 1-1) and Type 2, Level 4 (labeled 2-4) to compare a worst-case difference or the two extremes.
We decided to look at the minimum and maximum readings, take the difference between these two points, and compare each meter's average and standard deviation.
The above results show what we assumed would be the case.
Applying the minimum filter produced a result different from the maximum level of filtering.
However, the standard deviation of these two filters only varied on the 4215 Standard by 0.00001 mV/V.
The Average difference between the two options was about 0.00006 mV/V, or about 0.003 %.
The maximum deviation of the 22,000 plus readings was between 0.00020 mV/V to 0.00036 mV/V.
4215 PLUS Load Cell Meter Filter Settings Comparison
Applying the minimum filter produced a result different from the maximum level of filtering.
However, the standard deviation of these two filters only varied on the 4215 Plus by 0.00001 mV/V.
The Average difference between the two options was about 0.00005 mV/V, or about 0.0025 %.
The maximum deviation of the 22,000 plus readings was between 0.00003 mV/V to 0.00010 mV/V.
Conclusion Comparing Load Cell Meter Filter Settings on Morehouse 4215 Load Cell Meters
The filter settings can make a difference in the indicator readings.
The data speaks for itself on both of these meters.
The maximum difference in the average readings was about the same, from 0.0025 % to 0.003 %.
In addition, the 4215 Plus is a way more accurate meter than its predecessor.
The data speaks for itself on the improved performance, equating to about a 3-x improvement.
-Henry Zumbrun, Morehouse Instrument Company
About Morehouse Instrument Company
For more insights into force and torque calibration, metrology, and load cell reliability, explore our comprehensive blog at https://mhforce.com/blog/.
We believe in changing how people think about force and torque calibration in everything we do. This includes setting expectations on load cell reliability and challenging the "just calibrate it" mentality by educating our customers on what matters and what causes significant errors.
We focus on reducing these errors and making our products simple and user-friendly.
This means your instruments will pass calibration more often and produce more precise measurements, giving you the confidence to focus on your business.
Companies around the globe rely on Morehouse for accuracy and speed. Our measurement uncertainties are 10-50 times lower than the competition.
We turn around your equipment in 7-10 business days so you can return to work quickly, saving you money.
When you choose Morehouse, you're not just paying for a calibration service or a load cell.
You're investing in peace of mind, knowing your equipment is calibrated accurately and on time.
Contact Morehouse at info@mhforce.com to learn more about our calibration services and load cell products.
Email us if you ever want to chat or have questions about a blog. We love talking about this stuff.
Want to see the differences between a 4215 HS and a Standard 4215 using the same load cell meter filter settings?
That video can be found here.
# Load Cell Meter Filter Settings