QLA414 Manual

Mechanical Installation

The following items should be observed to avoid damage to the QLA414 sensor during installation and usage.

Avoid conditions that exceed the sensors IP rating.
Store in a dry area without fixtures.

Avoid contact to sensitive areas.

Delicate instrumentation, don't contact

Do not pull on or carry sensor by cable.

Monitor sensor output for effects on zero output during installation to avoid damage .

Avoid over torque during installation.

Maximum Installation Torque
Capacity	Max. torque
5 lb	1 in-lb
10 lb	1 in-lb

Maximum moments and off-axis loading

Extraneous load information can be used to assist in determining if the sensor can withstand any unavoidable off-axis loads and moments.
Extraneous how-to guide

Capacity

Equation: σ_max ≥ (A)Fx + (B)Fy + (C)Fz + (D)Mx + (E)My + (F)Mz

Material: 17-4 P.H. Stainless Steel

Capacity (lb)	A	B	C	D	E	F
5	13911	12770	4636	141109	201399	89968
10	7973	5799	2413	88743	105463	50734

All forces to be calculated using lb and in-lb units

σ_max Table
Material	Static Load (=60% Y.S.)	Fatigue (non-reversing loads)	Fatigue (full-reversing loads)
17-4PH S.S.	87,000	78,000	62,000*

*Value is 75% of Fatigue Strength based on 10 – 20 × 10⁶ cycles and allow for factors that influence fatigue such as surface finish, stress concentrations, corrsion, temperature and other variables for the production of the transducer. For infinite Fatigue Life (100 × 10⁶) use 75% of values shown.

Deflection & Natural Frequency

Capacity	Deflection (in.)	Natural Frequency (kHz)	β
5	0.00005	71	0.0002
10	0.00005	98	0.0002

Natural Frequency & Frequency Response Equations

Natural Frequency (FN) equals 3.13 times the square root of 1 over (beta divided by capacity times deflection) and results in a value in Hz. Frequency Response with Load (FR) equals 3.13 times the square root of 1 over ((beta plus AppliedLoad) divided by cacpacity times deflection) and results in a value in Hz.

Where β values are obtained by FUTEK engineers

Mounting and Installation

Below is information for proper mounting and installation. Refer to the sensor spec sheet for thread information and proper load cell orientation to maximize performance and limit cable interference.

Measurements are called out on the sensor spec sheet and have the following tolerances based on the number of decimal points present.

Decimal format	Tolerance
0.x	± 0.1" [2.5mm]
0.xx	± 0.01" [0.25 mm]
0.xxx	± 0.005" [0.127 mm]
0.xxxx	± 0.001" [0.0254 mm]

Mount sensor mounting surface first.

Mounting surface indicated in this diagram

Mounting Examples

In-line tension/compression

Bottom-mounted compression

In-line micro rope double-sided tension

In-line micro-rope/rod thru-hole compression

Cable Care and Routing

Below is information for proper cable care and handling. Cable material type and length can be found online in the sensor description page.

Attention and additional handling care are needed for OEM exposed cable

Sensor has small cable length. Avoid stress and movement on cable to avoid damage.

Properly secure sensor cable to limit cable movement influence.

Avoid folding or bending flex cable. Don't fold flex cable back.

Connecting sensor using FPC to LEADS adapter

Featured accessory: QSH02146
0.5mm pitch 4-pin FPC to flying leads 3 in. long cable converter

Always lift the connector gate during mating and demating sensor from the amplifier. Note: 0.5 mm flex connector has limited lifecycle. Limit mates/demates as much as possible.

Insert flex into connector with flex backer facing the connector gate.

Close the connector gate.

Electrical Installation

Wiring and connections

The QLA414 load cell series utilizes a four-conductor Flex cable.

Wire connections are + Excitation, - Excitation, + Signal, and - Signal. The coloring code for the QLA414 series connections are Red, Black, Green, and White.

Consult the sensor's online spec sheet for any further wiring information

QLA414 Excitation Power Levels: 5 VDC or VAC max.

Wiring Code WC8
Pin	Color	Purpose
A	Red	+ Excitation
B	Black	– Excitation
C	Green	+ Signal
D	White	– Signal

On the flex cable, pin A is closest to the mounting surface. Pin D is farthest from the mounting surface.

System Configuration Examples

Embedded multi-sensor

QIA125: Triple channel multiplexing digital system

Embedded micro-system

QIA128: Ultra low-power micro digital amplifier

PC-based SENSIT™ system

USB220: Digital amplifier SENSIT™ system

Shield Usage and Connections

Cable shielding should be grounded on one end, either the sensor side or instrument side to avoid ground loops.
A shield connection listed as floating on a sensors spec sheet means the cable shield is not connected on the sensor side and may be connected on the instrument side to ground.

Diagram describing the shield connection to the amplifier.

Calibration

A yearly calibration is recommended. But verification and calibration period shall be defined based on application, conditions, endurance and usage.
FUTEK offers NIST calibrations as well as A2LA certified calibrations for total uncertainty.
For more information on available calibrations visit FUTEK calibration web page at: https://www.futek.com/store-calibration
For recalibration orders visit the FUTEK recalibration page at: https://www.futek.com/recalibration
An online summary of calibration results is available at: https://www.futek.com/support/calibrationdata

Shunt

A shunt is an external resistance applied across two points on the load cell's Wheatstone bridge to generate a known, fixed output from the sensor.

Shunt results can be used to set up instruments as well as compare changes to the load cell output over time and usage.

When selecting the appropriate shunt resistance for your load cell, we recommend a resistance that generates an output of about 80% of the sensor's rated output. It is important to have a shunt resistance that results in an output that is less than the full output of the load cell.

Additionally, recommended shunt resistance levels may be available on the sensor spec sheet.

TEDS

Transducer Electronic Data Sheet (TEDS) IEEE1451.4 standard is available for FUTEK sensors and is utilized by select FUTEK instruments.

Through the use of TEDS load cell calibration information can be stored with sensor, or sensor cable, for use with TEDS capable instruments.

FUTEK utilizes the Bridge Sensor template 33 for the QLA414 family.

The following FUTEK instruments are TEDS and QLA414 compatible:

IPM Series
Panel Mount Display

IHH Series
Handheld Instrument

Troubleshooting

When troubleshooting, we recommend that the sensor be removed from any fixtures. In order to confirm that that sensor is operating correctly, we suggest placing the sensor on a firm surface, and to apply a known load.

We also recommend using a volt meter with a clean power supply to confirm the sensor is operating correctly.

Symptom	Possible Cause	Check	Repairability
High zero output	Sensor is under preload Sensor has been overloaded from too much load, off axis load, or moment. Sensor has experienced high cyclical load fatigue.	Fixtures or bolting stress for causes of pre-load. Loading and support placement for off axis loads. Avoid excessive moments during installation.	Overload shift would not be repairable. If zero offset is stable it may be possible to use sensor by use of Tare or subtracting zero from sequential readings.
Non-responsive zero output	Sensor or instrument is not powered. Sensor is not properly connected. Load is not displaced properly onto sensor. Sensor is not supported correctly and not allowing deflection to occur to measure load. Internal disconnect or short.	Power and wiring to sensor and instrument. Sensor bridge resistance for possible opens or shorts. Perform continuity test on cable. Load is placed correctly on sensor loading surface. Sensor loading surface is not obstructed or supported and able to flex under load. Sensor support is not giving while sensor is loaded.	Internal disconnections or shorts would not be available for repair. Sensor cable repair may be available if disconnect or short is not too close to sensor.
Non-responsive high output	Sensor is disconnected from instrument. An opening has occurred in sensor or cable connection. Sensor has been overloaded and deformed causing permanent high stress on internal gauges. Fixture, applied load, or mounting is causing a high pre-load on sensor.	Power and wiring to sensor and instrument. Sensor bridge resistance for possible opens or shorts. Perform continuity check on cable. Sensor zero output to see if sensor returns to zero or has a high zero load output due to overloading. Remove load and loosen mounting bolts or fixtures to check if sensor is being preloaded.	Overload shift would not be repairable. Internal disconnections or shorts would not be available for repair. Sensor cable repair may be available if disconnect or short is not too close to sensor.
Incorrect output for applied load	Load is not applied correctly to sensor loading surface or is off axis. Fixtures are not secure or obstruct loading. Sensor loading surface is not able to deflect with applied load. Sensor support is not ridged and firm. Incorrect sensor output is utilized.	Placement of load on sensor. Fixtures are not impeding ability to load. Support surface is not giving with applied load. Calibration verified outputs are being used.	Recalibration is available for confirmation of sensor performance.
Zero output drift	Unstable power supply, or noisy power supply, to sensor. Sensor exposed to temperature change. Sensor exposed to pre-load from fixture or mounting. Sensor exposed to liquid or humidity.	Stability of power supply and noise levels. For temperature changes or unevenly distributed temperature changes. Possible loose fixtures and bolts	Internal damage from liquid exposure is not repairable. Recalibration is available for confirmation of sensor performance.
Creep in output while under load	Load or fixtures are not stable. Power supply is unstable or noisy. Sensor is exposed to temperature change. Sensor support is not rigid and firm. Sensor exposed to liquid or humidity. Friction in assembly	Stability of power supply and noise levels. Fixtures for stability. For temperature changes or unevenly distributed temperature changes. Confirm support surfaces are not giving while under load.	Internal damage from liquid exposure is not repairable. Recalibration is available for confirmation of sensor performance.
Noisy or unstable output	Power supply is noisy. Load is not stable. Sensor or cable is placed close to high power equipment. Sensor or instrument is exposed to ground loop with other equipment grounds.	Power supply stability. Load is stable and fixtures are secure. Reroute cables away from high power equipment. Confirm wiring and grounds are not connected to unintended equipment ground.	There are no active electronics in a load cell, such as capacitors or IC chips that may contribute to noise.