Signal amplifier
Use this component when the task is to receive and condition a load-cell signal for a PLC, controller or display.[1][2]
Resources / Load Cell Signal Amplifier Selection
How to Select a Load Cell Signal Amplifier for Web Tension Control
A signal amplifier is the interface between a low-level load-cell signal and the controller, PLC or drive that uses the measured tension. Select it from the real sensor arrangement, required output, receiving device, calibration method and cabinet conditions—not from the amplifier name alone.
Tension measurement integration guide
Match the amplifier to the complete measurement loop
Use the sensor bridge, number of sensing points, output format, receiving device and commissioning method to create an amplifier specification that can be checked before installation. The hero is an AI-generated editorial illustration based on an approved KTC820D product-photo reference, not a documentary installation photograph.
1. Separate measurement, signal conditioning and power control
A web tension sensor measures the force at the measuring roller; a measuring amplifier conditions that sensor signal for a downstream device. KRD describes the KTC820D as a tension signal amplifier for LX sensors that provides 0–10 V, 4–20 mA and Modbus RTU outputs for PLC acquisition or display.[1]
Controller or power stage
Treat a tension controller and a brake or clutch power stage as separate functions unless the selected product documentation explicitly combines them.
2. Define the load-cell arrangement before selecting channels
Record the exact sensor family, bridge type, excitation requirement, rated signal, number of sensing points and the mechanical arrangement of the measuring roller. The FMS EMGZ491.ECAT manual is an example of why this matters: it is intended for one or two FMS load cells, and its two-sensor arrangement connects the cells in parallel internally.[2]
- Identify the sensor output and bridge data from the actual sensor documentation; do not assume that an mV/V value, excitation voltage or wiring scheme is universal.[1][2]
- Document whether the roller has one sensing point, two sensing points combined by the amplifier, or separate channels required for diagnostic purposes.[2][3]
- Confirm whether the proposed amplifier accepts the installed bridge and the required number of sensor channels before specifying the output or PLC interface.[2][3]
3. Match the conditioned output to the receiving device
The receiving device defines the useful output. KRD lists 0–10 V, 4–20 mA and Modbus RTU for the KTC820D; other amplifier families may offer different analog ranges, channel behavior or industrial-network interfaces. Compare the exact amplifier data sheet with the PLC, controller or drive input documentation before purchase.[1][3]
Analog loop
Confirm the required voltage or current range, scaling convention, input impedance or permitted load, and whether the receiving input is differential, single-ended or isolated as documented for the selected devices.[3]
Networked signal
If a PLC receives tension over a fieldbus, confirm the supported protocol, device file or configuration method and the required measured-value and status data.[2]
4. Include calibration, wiring and cabinet conditions in the specification
Commissioning is part of compatibility, not a final afterthought. The EMGZ491.ECAT manual calls for offset compensation before calibration and describes applying a defined load through the installed material path. It also specifies its own one- or two-sensor wiring arrangement and shielded, twisted sensor cable; those details apply to that product and must be replaced by the selected KRD equipment documentation during final engineering review.[2]
- List the zero or offset condition, calibration force method, measured signal scaling and acceptance reading required for the actual machine.[2]
- Record the sensor cable, shielding, grounding, power supply, enclosure, temperature and mounting constraints from the selected product manuals and local electrical requirements.[2][3]
- Escalate uncertain wiring, grounding, safety or PLC compatibility to the equipment supplier or a qualified controls engineer before installation.
5. Prepare a concise KRD review package
For a KTC820D, LX sensor or broader KRD tension-measurement review, provide the existing sensor model and label data, roller layout, number of sensors, desired tension range, current wiring, receiving PLC or controller model, required analog or network interface, cabinet supply and the calibration method. This makes it possible to review the complete signal path instead of treating an amplifier as a universal replacement.[1]
Sources & References
- KRD Industrial Solutions. KTC820D Tension Signal Amplifier Back
- FMS Force Measuring Systems AG. EMGZ491.ECAT Operating Manual Back
- Erhardt+Leimer GmbH. PA 62 Digital Measuring Amplifier with Display Back
FAQ
Is a load cell signal amplifier the same as a tension controller?
Not necessarily. A signal amplifier conditions the sensor measurement for another device. A controller uses the measurement in a control loop, and a power stage supplies an actuator such as a brake or clutch. Confirm which functions the selected product actually includes.
Can two load cells connect to one amplifier?
Some amplifiers are designed for two sensing points, while others use separate channels or a different arrangement. Confirm the sensor configuration and the selected amplifier's documented input method before wiring or purchase.
Should I choose 0–10 V, 4–20 mA or a network interface?
Choose the format the receiving PLC, controller or drive is documented to accept. Then verify scaling, electrical limits, protocol support and commissioning requirements across both pieces of equipment.
What should I send KRD for amplifier selection?
Provide sensor model and label data, number of sensors, machine section, roller layout, existing wiring, desired output, receiving PLC or controller model, cabinet supply and intended calibration method.
Request a tension-signal interface review
Share the load-cell model, number of sensors, present wiring, required PLC or controller input, cabinet supply and calibration plan. KRD can help review the measurement signal path before a replacement or new-build decision.