The Micro-Tech 9106 is not a belt weigher integrator. It reads the force of material falling onto an impact plate inside a chute and turns that into a rate in t/h and a running total, with no belt, no speed sensor and no load cells anywhere in the chain. That one difference changes the alarms, the calibration, and most of what goes wrong.
What is a Micro-Tech 9106, and how does it differ from the belt scale models?
It is the electronics for an impact flow meter, also called a solids flow meter or an impact weigher. Material leaves a chute, strikes a sensing plate, and the deflection of that plate is the measurement.
The sensing element is not a strain gauge load cell. It is a displacement transducer with its own preamplifier, reporting as a frequency rather than a few millivolts, roughly 100 to 2,500 Hz. That signal carries about 300 metres and shrugs off noise that would ruin a bridge signal. The trade off is that the familiar diagnostics do not apply: no sense jumpers to get wrong, no cell to lift out of a summing box, no millivolts to measure. Nor is there a speed input, so rate comes from force alone.
We are an independent service company, not Thermo Fisher and not a Thermo Fisher agent. For the conveyor integrators in the same family see Micro-Tech 9101 and 9201 error messages and calibration; for the feeder controller see Micro-Tech 9105 and 9205 weighfeeder control.
Impact meters are a smaller part of our work than belt weighers, but we can help with them: the sensor, the chute installation and the integrator together. Not every sensor or preamplifier for an older meter is still available, or worth the price when it is, but we will always have a replacement option at a sensible price through the arrangements we have with suppliers across the industry.
What do the common Micro-Tech 9106 alarms mean, and which ones stop the plant?
Any of them can, because each alarm is configurable to warn, to shut down, or to be ignored. An alarm only clears on reset if the condition has gone, and the numbering is model specific: the same condition carries a different number on the belt scale and weighfeeder versions. Trust the words, not the number.
Bad weight signal. No valid frequency is arriving from the impact sensor. Check terminations at both ends before suspecting the transducer or its preamplifier. This is the 9106 equivalent of a load cell failure, and a call out if the wiring checks clean.
Auto zero tracking over limit. The automatic zero trim wanted a bigger correction than it is allowed, so it refused and alarmed instead. That nearly always means build up on or under the plate. Clean it, let it settle, and if it returns straight away stop resetting it (why a zero drifts).
Cold start. The setup data did not survive a power loss, usually a flat memory backup battery. Always a call out, because it is a recommission, and the first question is who holds the calibration record for every product.
Power lost during a calibration. The routine never finished, so the meter may not be calibrated at all. Run the check again and compare against the last record before trusting the totals.
High and low flow rate. Process alarms the site sets itself against a percentage of capacity, delayed so a surge does not trip them. A low rate alarm with material visibly running is a measurement problem.
Calibration time elapsed. A reminder timer set in days, which will not clear until a calibration check has been run. Treat it as the meter doing its job.
Communication errors, fieldbus watchdogs and math errors behave as they do across this family.
What does a 9106 calibration involve, and why must the span use real material?
Isolate and lock out the plant to your site procedure first, and treat the enclosure as live: a field mounted unit runs on mains. This is work for trained, authorised people. Then it is zero, span, and a check.
Zero. The counterintuitive step, and the one most often done wrong. Material flow must be completely stopped, but everything else around the sensor should be running: screw conveyors, rotary airlocks, the bucket elevator, dust collection. All of that puts vibration into the structure, and vibration is part of what the plate reads. Zero on a shut down plant and you have taught the meter a reference it will never see again.
Span. There is no electronic shortcut, which is the biggest single difference from a belt weigher. Every material rebounds off the plate differently, so a resistor that fakes a load tells you nothing about how yours behaves. The span has to be a material test: run at the maximum rate the meter will normally see, hold it steady for at least five minutes, and move enough material to matter, which the documentation puts at two hundred of the smallest total increments, or twenty tonnes on a meter totalising in tonnes. That material is then weighed on an accurate static weighing device and the true figure entered. Test weights and chains have no equivalent here (calibration methods compared).
The discipline. Accept a new zero or span on the first setup only. After that, run the test, record the error and decline the change, because repeat tests measure repeatability and a meter that cannot repeat has a problem no adjustment will fix (zero, span and repeatability explained). Switch linearisation off first or the correction factors fight the test.
Why does a 9106 hold a separate calibration for each product, and what does linearisation add?
Because the impact force depends on what is falling, not just how much. Change the bulk density or the size distribution and the same tonnes per hour hit the plate with a different force, so a span that was right for one material is wrong for the next. The 9106 answers that with numbered product recipes, up to ninety nine of them, each holding its own span, linearisation and zero. Each is calibrated the first time that material runs, after which selecting the product, locally or through a digital input from the plant, recalls the right numbers. A useful cross check falls out of it: the zero should not change with the product, and if it does, something mechanical has moved.
Linearisation handles rate rather than material. Zero and span are set at the top of the range, so a meter that spends long stretches well below capacity can be honest at full rate and out at low rate. Up to five correction factors can be taken across the range, all below the span rate.
Why does an impact flow meter drift or start reading low over time?
Nearly always because the material stopped hitting the plate the way it did on the day it was calibrated. Build up on the plate or in the chute beneath it is the first thing to check, and the daily job worth giving somebody. After that comes anything that changes the drop: a worn liner, a shifted deflector, a blockage upstream, a feed running to one side. None look like an instrument fault and every one moves the reading.
Two features exist to fight this. An air purge output fires on an interval for a set duration to keep the sensing area clear, and it is worth confirming yours still works rather than assuming. Where water content varies, an analogue input can take a moisture signal and compensate against two known points. That compensation is suspended during a material test so the totalised figure compares directly against the static weight, which is right, but it does mean a compensated meter and its calibration record describe slightly different things. The rest are the ordinary electrical causes (protecting the electronics).
How does a 9106 connect to the plant, and what can it switch?
Through more outputs than most sites use. Alongside a current output for flow rate there are programmable digital outputs for a ready signal, a fault contact, cumulative alarm and shutdown, a totaliser pulse, the air purge and spare custom points. Digital inputs can reset totals and alarms, trigger a zero and select the product. On the data side, two serial ports run Modbus, Allen-Bradley DF1 or Siemens 3964R, a built in Ethernet port carries Modbus TCP and EtherNet/IP, and Profibus DP is a plug in board (getting weighing data into your PLC or SCADA).
One detail saves a call out: the ready output is only on when the meter is calibrated and nothing has shut it down, so it drops the moment somebody starts a calibration.
Where do you get the Micro-Tech 9106 manual, and what about access codes?
The trap on this one is the family name. Micro-Tech covers boxes that do completely different jobs, so a search for a 9106 manual will just as happily hand you a 9101, 9201 or 9105, and those describe a span set with test weights or an electronic reference, which is no use on a meter that can only be spanned on material. Alarm numbering moves between the models too, so the same condition sits under a different number. The documents themselves are Thermo Fisher’s, and they live with Thermo Fisher or with whoever supplied your meter; we do not keep copies here. What we can do is answer the question you were going to open the manual for, because our technicians work from the full documentation and keep a configuration record for the instruments we look after, which on a 9106 means the span for every product.
Photograph the nameplate and the screen before you start searching: the model as printed, the serial beside it and the software version the meter reports are what separate a 9106 from the rest of the family. Product recipes and linearisation points were redefined between revisions of this meter, so a document one generation out has you running a routine yours does not have, and we would rather sort that out in two minutes than have you work from it. Access codes are the one thing we will not supply and nobody else should either: the 9106 holds protection levels over its setup and calibration data and an audit trail of every change affecting weighing, so if you are locked out see locked out of your integrator?. The contact us form will carry those photos, admin@accurateindustries.com.au will take them just as well, and 1300 101 666 gets you a technician on the phone if the meter is alarming while you stand there.
When should you call us rather than keep resetting a 9106 alarm?
Call when the alarm comes straight back, because that is the meter saying the condition never went away. Call on a bad weight signal that survives a wiring check, on a cold start, on a zero that will not settle after the chute has been properly cleaned, and on a reading that has drifted with no obvious cause. Call sooner if nobody holds the calibration record for each product, because that turns a straightforward visit into a recommission. And call before anyone opens the enclosure (booking a service).
Frequently asked questions
Can a Micro-Tech 9106 be calibrated without running material?
Not the span. The zero can be done whenever flow stops with the surrounding plant still running, but the span depends on how your material rebounds off the plate, so it can only be set by running material and weighing it.
Why does my flow meter read correctly on one material and badly on another?
Because it was calibrated for one of them. Different bulk densities and particle sizes hit the plate with different force at the same tonnes per hour. The meter holds a calibration per product, but each has to be established the first time that material runs.
The rate looks right but my totals are stuck on zero. What is wrong?
Most likely the meter was never spanned, or a calibration was abandoned partway. An uncalibrated 9106 shows an indicative rate while refusing to totalise, so nobody builds a shift report on a number it will not stand behind.
Is an impact flow meter as accurate as a conveyor belt weigher?
They are different jobs. An impact meter measures flow where there is no conveyor to put a weigher on, in a chute or a downpipe. A well maintained belt weigher on a good frame will generally do better where both are genuine options (types of belt weighers).