LTE DIN Rail Analog Transmitters with Ethernet Communication and Analog outputs for Weighing Applications

LTE Weighing Transmitter Frequently Asked Questions

Why would someone choose the DC signal conditioner board over the load cell board for a weighing application, given the load cell board's finer resolution?

The page documents this as an available configuration choice without specifying selection criteria beyond the two boards' differing sensitivity — since the DC board's most sensitive range (±200 mV, 10 µV resolution) is coarser than the load cell board's most sensitive ranges (±20 mV/±50 mV, 1 µV resolution), the DC board would be the documented choice specifically when a load cell or bridge signal is strong enough that the finer, more sensitive load cell board isn't required.

Does the relay setpoint offset feature require re-calibrating the scale's two-point zero/span calibration when the offset value changes?

The page documents these as two separate, independently configured functions — two-point calibration (LO IN/HI IN) establishes the fundamental relationship between signal and displayed weight, while relay setpoint offset is documented as a separate adjustment to when the ON/OFF control action fires relative to a setpoint; since offset governs control timing rather than the underlying weight reading itself, changing the documented offset value is consistent with not requiring the separate two-point calibration to be redone.

Why does the fixed right-hand dummy zero feature specifically preclude the use of decimal points?

Documented description specifically ties this feature to shifting the display to allow values up to 999,990 by fixing a zero to the right — since the display has a fixed number of digit positions, dedicating one to a fixed trailing zero to extend the displayable range necessarily uses up the position that would otherwise be needed for a decimal point, which is the documented reason this specific range-extension method comes at the cost of decimal display.

What specifically happens if the auto-zero limit is left at its default rather than explicitly set to 0 to disable it?

Documented description specifically states auto-zero compensates for load cell drift whenever the transmitter comes to rest within the programmed limit (0 to 9 counts) from zero — this indicates that unless a user explicitly enters 0 to disable the function, auto-zero remains active at whatever nonzero limit is configured, automatically re-zeroing within that band whenever the scale is at rest, which is the documented default behavior a user should be aware of if that automatic re-zeroing isn't desired.

Does the coordinate reading calibration method require the actual physical weight used during calibration to be known precisely by the user in advance?

No — documented description specifically distinguishes this from the manual coordinate method by noting the transmitter itself reads the actual high and low signal values during the coordinate reading method, with the user separately entering only the desired corresponding reading values; this is consistent with the coordinate reading method being suited to situations with an external calibration reference providing the actual physical values, since the transmitter captures the real signal directly rather than requiring the user to have pre-measured input voltages.

Can more than four 350-ohm load cells be connected to a single transmitter if additional excitation current is supplied externally?

The page documents the built-in excitation supply specifically as rated 120 mA at 10V, sized to power up to four 350-ohm load cells in parallel — while the page doesn't explicitly address supplementing this with external excitation, the documented four-cell figure is presented as tied to this specific supply's current rating, so exceeding it would be inconsistent with the documented capacity of the standard built-in excitation output as specified.

Does selecting WM1 custom scaling change the documented 0.01% of full scale ±2 counts accuracy figure from the standard WM option?

No — documented WM1 option describes custom scaling (specifying min/max input and corresponding min/max displayed reading across a 20-500 mV span) as a configuration choice for how raw signal maps to a displayed reading, not as a change to the underlying signal conditioning accuracy; both WM and WM1 use the same documented load cell signal conditioner hardware and share the same documented accuracy specification.

Does this LTE weighing transmitter's documented Ethernet-only communication mean it cannot be daisy-chained with other transmitters the way LT Series RS485 units can?

Correct as documented — the page describes LTE series Ethernet transmitters as connecting directly to a LAN via an Ethernet cable, distinct from the documented RS485 daisy-chaining of up to 30 LT Series transmitters; multiple LTE units would instead each connect individually to the same Ethernet network/switch rather than being physically daisy-chained together in the way documented for the RS485 LT variant.

Does the transmitter's documented power consumption figures (varying from 2.4W to 3.35W depending on supply voltage) affect weighing accuracy?

No — documented power consumption figures describe the transmitter's own electrical draw at different supply voltages when powering four 350-ohm load cells at 10V excitation, a separate specification from the documented 0.01% FS ±2 counts accuracy figure; power consumption variance across supply voltage options reflects the transmitter's own internal power regulation, not a factor documented as affecting the underlying weight measurement accuracy.

Can the Extended board's custom curve linearization be combined with the weighing-specific firmware features (count-by, auto-zero, setpoint offset) on the same transmitter?

The page documents the Extended board as an option available at the Main Board ordering level, separate from the Signal Input selection (P/P1/SG/SG1/WM/WM1) that determines the specific weighing firmware behavior — since these are documented as independent ordering selections rather than mutually exclusive options, choosing the Extended main board is consistent with being combined with any of the documented weighing-specific signal input configurations.

Legal-for-Trade & NTEP Scale Certification Questions From the Field

What does "legal for trade" specifically mean for a commercial weighing application?

Documented definition specifically ties this designation to any commercial transaction where a product's price is determined by its final weight — such as a deli counter, scrap yard, or shipping application — with documented requirement that the scale used in such a transaction must be NTEP certified and sealed so its calibration cannot be tampered with, specifically to keep the transaction fair to both buyer and seller.

What specifically is NTEP, and what governing document defines its technical requirements?

Documented explanation specifically identifies NTEP as the National Type Evaluation Program, managed by the National Conference on Weights and Measures (NCWM); NTEP certified scales are documented as required to meet technical and performance standards specifically outlined in NIST Handbook 44, covering aspects such as capacity, accuracy, and performance under varying environmental conditions.

Is NTEP certification of a scale model alone sufficient to make an individual physical unit usable for legal-for-trade transactions?

No — documented guidance specifically clarifies that NTEP certification confirms the scale model meets national design standards, but the individual physical unit still requires separate field verification and sealing by the applicable state's weights and measures authority before it can be legally used for commercial transactions; NTEP is documented as a national, model-level certification, distinct from the required local, unit-level field inspection and sealing step.

Does relocating or repairing an already-certified legal-for-trade scale affect its certified status?

Yes — documented guidance specifically states re-certification is required after relocation, repair, or calibration drift, and that a valid physical seal (checked by inspectors during audits) is what confirms the certification remains intact; a scale lacking that seal, even if it's an NTEP-approved model, is documented as failing inspection despite the underlying model-level certification still being valid.

Are legal-for-trade certification requirements uniform nationwide, or do they vary by state and jurisdiction?

They vary — documented guidance specifically notes that while NTEP is a national program, rules and regulations for legal-for-trade enforcement genuinely vary by state and county, with separate state-level weights and measures authorities responsible for field inspections, sealing, and enforcement; documented advice specifically recommends confirming requirements with a registered service agency familiar with the applicable local jurisdiction rather than assuming one statewide rule applies everywhere.

Are there documented industry-specific certification methods distinct from general NTEP certification for certain weighing applications?

Yes — one documented example specifically describes a California-only Caltrans test method (CT-109) used specifically for batch-plant and hopper scale calibration on construction materials projects, explicitly documented as serving a different purpose from general NTEP certification and not interchangeable with it.

Does a scale's minimum graduation size (count-by increment) factor into legal-for-trade or NTEP evaluation?

Yes — documented NTEP evaluation criteria specifically cover a scale's accuracy and performance characteristics as outlined in Handbook 44, which documented industry sources describe as governing exactly this kind of resolution/graduation characteristic; a scale's minimum legally usable graduation size is part of what NTEP-approved laboratory testing is documented as verifying before a Certificate of Conformance is issued.

Do legal-for-trade requirements apply differently to industrial-floor scales compared to retail-counter scales?

The core certification requirement (NTEP approval plus proper sealing and field verification) is documented as applying to both, though documented guidance separately notes each environment drives different physical design needs — retail counters favor a compact footprint, bright display, and easy-clean surfaces, while industrial floor scales are documented as needing a rugged build, overload protection, and high-capacity load cells to survive their respective operating environments.