8 popular moisture meters put to the test

 Trading in the old moisture meter for a slicker new model won’t have been at the top of many farmers’ to-do lists this harvest.

Let’s face it, giving the combine’s wheezing air-con a bit of attention or getting those chunky flotation tyres for the trailers will be a lot more pressing.

But buying a decent tool to help you cut at the right time and only dry as much as you have to will have a considerably more exciting impact on your back pocket.

Tap a search into Google and you’ll be flooded with options from £250 to well over a grand. But which should you go for? Grinding? Whole-grain? Cheap? Expensive?

We’ve done the hard work for you by getting our hands on eight of the most common ones.

How we tested them

Step one was to give each moisture meter a thorough going-over on farm.

Working our way through a bucket full of wheat gave a good indication of how easy they were to live with and showed us just how variable the readings can be between machines. The next step was to do what most farmers say they do on their annual Assured Combinable Crops Scheme (ACCS) form – take them to a moisture meter clinic.

We picked a session hosted by Dengie Grain near Maldon, Essex, which was run by grain testing aficionado Jo Cauvain of Tendring Lab Services.

Straight out of the box they were put to work on Jo’s certified samples. These included hard wheat, soft wheat, conventional oilseed rape, hybrid oilseed rape and peas, all with varying moisture contents.

Some meters were way off the mark and others weren’t too bad. But once we’d made a couple of adjustments they were all giving satisfactory results.

Two machines did stand out in the out-of-the-box accuracy test, though – Martin Lishman’s Protimeter and the Unimeter Digital.

These are both calibrated in the UK and the Unimeter Digital even comes with a certificate to show that it has been calibrated by Openfield.

This did make a difference as both returned pretty consistent readings straight off. The Protimeter was the most accurate on cereals and oilseeds, but it was a tad wayward on the peas.

Some churned out readings as low as 12.8% for a 15.3% wheat sample, while others said peas at 16.7% moisture were as high as 18.8%.

After calibration they were all giving satisfactory readings, so it definitely pays to get them checked over every now and again – even if you’ve got a brand new model.

GRINDING MOISTURE METERS

The following four meters crush or grind and compress the sample before taking a reading. This means they tend to give more consistent results than whole-grain meters as the moisture content is constant throughout the sample. The downside it that they’re more of a faff to use and there’s a bigger margin for operator error.

Wile 78 The Crusher – BEST FOR: 
EASY GRINDING

Made by Farmcomp OY, Finland

Sampler type 
Integrated grinding head

Sample size 9ml

Manufacturer’s claimed accuracy +/- 0.5%

Crops it can test 
Twenty-three pre-programmed crops as well as an arbitrary scale

Additional features 
Calculates sample averages

Moisture measurement range Grains: 9-38%, Oilseeds: 5-30%

Wile-Crusher

Ease of use The Wile 78 was the simplest grinding moisture meter to use by some margin. Samples are measured into the crusher using the built-in scoop and you grind and crush the grains by screwing the lid down. The grinder mechanism is similar to the one on the Unimeter Digital, but it’s much easier to turn and there’s an obvious stop position. The backlit screen is easy to use, too, and it’s quick to deliver a reading.

Carrycase It comes with a tough, padded fabric case that has a shoulder strap. There’s also space inside the case to fit a Wile 65 whole-grain meter.

Calibration process Individual crop calibrations are easy to tweak, but well enough hidden to stop unwanted adjustments.

Battery 1 x 9V

From APM

Price £365 plus VAT

Verdict The Wile 78 was our favourite grinding meter to use. The crushing head was almost as easy to turn as a whole grain meter and it didn’t need any extra paraphernalia for measuring out samples. It was also neat to carry around and the backlit screen was easy to see.

Picking gunky oilseed rape out of the grinding teeth was less pleasant, though, and it didn’t seem to grind the sample as fine as some others.

We didn’t think the grinding mechanism was as strong as the Unimeter either, and we did have to makes some adjustments to the calibration.

Likes

Clear backlit display

Scoop built into lid and easy to grind

Simple to use

Gripes

Not as fine a grind as the Unimeter or Martin Lishman

The grinding mechanism doesn’t look as strong as the one on the Unimeter Digital

Needed some adjustments to the calibration

Unimeter Digital – BEST FOR VALUE

Made by Farmcomp Oy, Finland

Sampler type Grinding

Sample size 9ml or 11ml

Manufacturer’s claimed accuracy +/- 0.5%, but Openfield calibrates them to +/-0.3%.

Crops it can test Thirty-one pre-programmed crops and an arbitrary scale

Additional features 
Calculates sample averages

Moisture measurement range 
Grains: 10.4-39%, Oilseeds: 5.4-25%

Unimeter-Digital

Ease of use The grinding mechanism isn’t for the limp wristed – after putting 20 samples through we were flagging. It’s also not obvious how far you have to wind it in so reading the instructions is a must. These are pretty clear though. The screen is also easy to use.

Carrycase Hard plastic case.

Calibration process Calibration is simple, but you’ll need to glance at the instructions.

From Agricultural Supply Services

Battery 1 x 9v

Price £345 plus VAT

Verdict If you’ve got a lot of samples to work through you’ll get a bit fed up with the grinding head on the Unimeter. According to UK importer Agricultural Supply Services a lot of farmers fashion a lever to help get a bit more purchase on it. The plus side is that this gives a finer grind helping it to be one of the most accurate straight out of the box. It also comes set up and calibrated for UK crops.

The electronics are basic and easy to use, too, and the sample measuring scoops are incorporated into the grinding head. It’s also pretty reasonably priced.

Likes

Gives consistent readings on most crops

Electronics are easy to use

Every model is calibrated by Openfield 
before it’s delivered

Gripes

Very difficult to grind sample

No backlight on display

Hard to know when sample is ground enough

Protimeter Grainmaster i-S – BEST FOR ACCURACY

Made by Martin Lishman, Taunton, England

Sampler type Grinding, with detachable grinder and compressor unit

Sample size 10ml

Manufacturer’s claimed accuracy +/- 0.5%

Crops it can test Fifteen pre-programmed crops, a 0-100 scale and 30 reference calibrations

Additional features Optional external moisture and temperature probes. Spares packages available

Moisture measurement range Wheat: 
11.3-29.3%, OSR: 7-26%, Barley: 10.9-29.3%

Protimeter-Grainmaster-i-S

Ease of use The grinder and compressor unit is a bit of a fiddle and you need to read the instructions to make sure you’re using it properly. Once mastered it’s easy to grind and obvious when the sample has been milled enough.

You need a 10ml spoon to get the correct sample size, which is too easy to lose. The box itself is easy to use.

Carrycase Hard plastic carrycase.

Calibration process It’s easy to add in calibration adjustments for each crop (if you’ve read the instructions) and there’s a warning to tell you they’re active. You need to watch that you don’t adjust them by mistake, though.

From Martin Lishman

Battery 1 x 9V and spare in case

Price £526 plus VAT including a free service

Verdict The Protimeter is probably the most common moisture meter in the UK and it was a solid performer in our tests. Sample prep isn’t the most straightforward, but when it’s new it’s easier to grind than some others. Blades do wear out, though, and if you don’t replace them it’s a pig to turn and doesn’t mill the sample properly. There is a spare set in the case and extras cost £26 plus VAT. The rest of the unit is easy to use and returned some of the best results in out out-of-the-box accuracy test. It’s not the cheapest though.

Likes

Consistent readings on grains and oilseeds

Obvious when the sample is ground

Easy to replace wearing parts

Gripes

Grinding and compressing is a bit of a performance compared with some others

Blades wear out

Separate plastic sample spoon 
and Wile Crusher

Easy to adjust calibrations when you don’t mean to

Riceter F508 – BEST FOR CLEAR SCREEN

Made by Kett, Japan

Sampler type Crushes a small number 
of grains with a screw head

Sample size Very small – roughly 14 grains of wheat

Manufacturer’s claimed accuracy +/- 0.5%

Crops it can test Twelve pre-programmed crops and no arbitrary scale

Additional features Averages can be calculated for up to nine test readings, after which it resets. These are also only remembered for five minutes

Moisture measurement range 
Cereals: 9-30%, Oilseeds: 6-22%

Riceter-F508

Ease of use The screen is easy to navigate and it’s quick to get a test result. The small sample means less time needed to rub out grains, but this won’t be as representative as a bigger one. The tiny sample trays are also a fiddle and are too easy to lose. In the instructions it says peas and beans have to be crushed with pliers before they are loaded into the sampling chamber. However, importer Farm-Tec says a single pea or bean can be loaded whole.

Carry case Small hard plastic case that houses all components.

Calibration process It’s possible to calibrate the meter for different crops, but it’s definitely one to do with the instruction book close by.

From Farm-Tec 

Battery 4 x AA

Price £295 plus VAT

Verdict We mentioned the Riceter to a few people in the know and it didn’t get the most glowing reviews. But we quite liked it.

The display was the clearest on test and the small sample size means you don’t have to spend hours rubbing out samples.

Accuracy didn’t seem to be a problem on well-conditioned grain, but you’d probably need to average a few tests at harvest. There are also a few too many bits and pieces to go missing.

Likes

The clearest screen on test

Easy to crush and compress sample

Quick to give a result

Gripes

Having to slide in small sample trays that 
are easy to lose

Tiny sample size won’t be as representative as some others

Difficult to alter crop calibrations


WHOLE-GRAIN MOISTURE METERS

Whole-grain meters simply compress the grain sample in order to get a reading. So no tough and tedious grinding and no mess to clear up at the end. They work well with conditioned grain, but are not so consistent at harvest time when moisture content varies. This means you should always take an average.

Wile 65 – BEST FOR: EASE OF USE

Made by Farmcomp Oy, Finland

Sampler type Compressing head

Sample size 65ml

Manufacturer’s claimed accuracy +/- 0.5%

Crops it can test 
Sixteen pre-programmed crops and 
an arbitrary scale

Additional features Calculates test averages. Optional temperature probe

Moisture measurement range Grains: 8-35%, Oilseeds: 5-25%

Wile-65

Ease of use Simple. Just scoop crop into the chamber and level off. Then turn lid until metal disc becomes flush with top of lid. This requires little effort. Just two buttons to flick through to choose crop type and carry out the test.

Carrycase Thin plastic box.

Calibration process Calibrations for each crop are quick and easy to adjust. The problem is that they’re easy to erase too.

From APM 

Price £335 plus VAT

Verdict The canister-style metal body is small, easy to hold and feels tough enough to carry around without the case. The compressing head is well made, too, and it didn’t get bunged up with grains. The screen is a bit old-school and could do with a couple more buttons though. Some readings were a bit erratic, but the average was pretty good in conditioned grain.

Likes

Really easy to use

Handy size

Good build quality

Gripes

Slightly old-school display

No backlight on screen

Easy to adjust calibrations 
by mistake

Mini Gac Plus – BEST FOR: EXTRA FEATURES

Made by Dickey-John, Illinois, USA

Sample type Whole-grain meter without compressor

Sample size Big

Manufacturer’s claimed accuracy +/- 0.5%

Crops it can test Nine crops are stored on the machine out of the box, but there are more than 450 different calibrations that can be loaded in from the PC software.

Additional featureS Averages of up to 20 samples are stored on the machine and the data can be downloaded to a computer. It also calculates specific weight.

Moisture measurement range Wheat: 8-34%, Barley: 8-29%, OSR: 6-21%

Mini-Gac-Plus

Ease of use The Mini Gac is pretty easy to fathom, but it is a bit of a faff to use. Before every reading you have to carry out an empty cell test to make sure it’s zeroed. The jug also has to be level or it won’t work. There’s no grinding to be done, but you need a big sample to fill it.

Carrycase Padded canvas; tough and well made.

Calibration process This can be adjusted via the keypad on the machine.

From Farm-Tec 

Battery 1 x 9V

Price £620 plus VAT; for more modest budgets, try Dickey-John’s £450-plus-VAT Mini Gac that calculates moisture content only.

Verdict With its specific weight calculation and mountain of extra features, the Mini Gac plus is in a slightly different league to the other whole-grain meters on test.

If you’re willing to take the time, you could probably get a lot out of it, but we found it a bit tedious when taking readings on the fly. The large sample size also means it isn’t suitable for rub-outs. We think it’s one to keep at the grain store and have another more portable meter to take to the field.

Likes

Neat for a higher-end device

Gives a hectolitre weight reading

Screen easy to read and navigate

Gripes

Size of sample

Having to carry out empty cell tests before each reading

Takes time to get the most from it

Agripro 6095 – BEST FOR: HANDY SIZE

Made by Sinar, England

Sampler type Compressing head

Sample size 65ml

Manufacturer’s claimed accuracy +/- 0.5%

Crops it can test Nineteen pre-programmed crops and an arbitrary scale

Additional features Works out test average and displays to the right of current test reading

Moisture measurement range 5-45% moisture range

Agripro-6095

Ease of use The Agripro’s compressor was harder to turn than other similar models and we found it a bit too easy to cross thread. Grains also tended to get stuck inside the compressing cap. On the plus side it’s neat, lightweight and the screen is easy to fathom.

Carrycase Hard plastic case.

Calibration process Calibrations are simple to adjust without reaching for the instructions.

From Evans and Pearce

Battery 1 x 9V

Price £459 plus VAT

Verdict For a premium-priced product, the Agripro fell a little short. The electronics were simple and easy to use, but we felt the compressor wasn’t as well made as some others. It only took a few seconds to load the sample, but we then spent time fishing grains out of the compressor mechanism.

It’s neat to carry around, though, and the buttons and screen also look like they’ll keep 
the dust at bay. Sinar also makes a grinding version called the Farmpro, which has a similar mechanism to the Wile Crusher and Unimeter.

Likes

Handy size

Simple 
to use

Dust-busting buttons

Gripes

Grains get stuck up side of compressor unit

Expensive compared with other similar meters

Easy to cross-thread the cap

MT-Pro – BEST FOR: TIGHT BUDGETS

Made by Agratronix, USA

Sampler type Compressing head

Sample size 65ml

Manufacturer’s claimed accuracy +/- 0.5%

Crops it can test Forty-nine pre-programmed crops

Additional features Backlit display

Moisture measurement range Different for all crops but white wheat moisture only goes up to 22%

MT-Pro

Ease of use Straightforward to use with a sample cell that’s almost identical to the Agripro and Wile 65. It’s quick to get a reading, but the large list of crops on the display is tedious to scroll through. Crop types are US-focused and it isn’t obvious which settings to use in the UK.

Carrycase Wraparound canvas case designed to stay on the meter when in use.

Calibration process Crop calibrations can be adjusted in the screen, but it’s not that easy and the instructions are poor.

From Brian Robinson Machinery

Price £246 inc VAT

Verdict The MT-Pro was the cheapest meter on test by some margin and it did feel a bit more flimsy than the competition. That said, the compressing head was almost identical to the more expensive Wile 65. There are plenty of buttons, but they don’t make the tricky menus any easier to navigate. You’ll see it with lots of different branding. Ours came from BRM, but had Sparex stickers on it.

Likes

Easy to fill sample

Lightweight

Big rubbery buttons

Gripes

Confusing menus

Feels cheap

Two 9V batteries needed – the others take one

Moisture meter dos and don’ts

Whether your moisture meter’s shiny and new or a tad careworn there are a few important steps you can take to get more accurate results. Grain testing expert Jo Cauvain runs through the basics.

Do:

  • Check your meter out at a moisture meter clinic or against test samples annually
  • Learn how to use it properly – I see lots of people using their meters incorrectly, which means they never return accurate results
  • Make sure all residues are removed before testing new samples – this is particularly important with some grinding meters that get residues stuck in their teeth
  • Use the sample measuring spoon or scoop to fill your moisture meter – different-sized samples give different results and the meter has been calibrated for one particular size
  • Take two or more readings and calculate an average – this is particularly important for whole-grain meters that tend to give less consistent readings
  • Use a 0.5% safety margin.

Don’t:

  • Keep your moisture meter in an air-conditioned combine cab or in direct sunlight as it needs to be at roughly the same temperature as the crop – for the most accurate readings the meter and sample should both be about 20C
  • Load your moisture meter with a dirty sample – any chaff in the sample will cause the meter to read about 0.5% lower than it should
  • Handle the sample too much – dirty, sweaty palms will skew the readings
  • Keep using a damaged of heavily worn meter – worn-out grinders are a particularly common occurrence and will give inaccurate readings as well as being a pain to use
  • Use your meter while holding or perched on uneven surfaces – they are most accurate on a firm, level base.