Hardy C2® Certified Cable has been designed specifically for the electrically and mechanically harsh environments found in Process Weighing applications. While many process variables are transmitted at a 0-10 volt or 4-20 milliamp level, signals from load or force sensors are typically one thousand times smaller, or 0-0.010 volts.
A ten-pound change on a 100,000-pound scale would correspond to a signal change of 0.000001 volts (1 micro volt). Therefore, cabling must protect against electrical noise common in the plant environment.
It is also imperative that moisture not enter the cable as it would increase capacitance and allow coupling of voltage from the excitation wires to the signal wires. The coupling of voltage causes “drifting” weight indications. Use of improper cable between even the finest load sensors and instrumentation will yield poor weighing results.
C2 is FAST
- Calibrates with ONE reference point, not FIVE
C2 is SAFE
- Eliminates need for full-scale test weights
C2 is RELIABLE
- Data stored in sensor chip & on the cloud
Hardy’s C2 uses calibration data downloaded into the memory chip that is embedded into each sensor. The Hardy instrument then reads the sensor performance characteristics off the chip enabling calibration. Unlike calibration with test weights, all the live weight on the scale does not have to be removed and heavy test weights do not have to be repeatedly put on and off the scale. As soon as your scale system is installed, it can be C2 calibrated, and proper scale installation verified. The result is electronic calibration that is easier, quicker, safer, and typically more accurate than methods used in the past.
What is included in a C2 system?
A C2 system includes load points, junction box, cabling and instrumentation, and is designed to make calibration easier than ever before. Upon installation or re-calibration, your Hardy instrument automatically searches for C2 certified load points and records their performance characteristics. Entering a reference point is all that’s needed to bring your system on-line within seconds.
All that’s left is to verify your scale. This is done by carefully distributing one or two small weights (depending on the capacity 5 to 100 lbs.) on to the scale so they are shared by all the load sensors. The scale reading should equal the value of the test weight/s applied. Remove the weight/s and the scale reading should return to its original value. If both of these are true then the scale is calibrated, verified and ready for use. If the values are not true, then there are potentially mechanical problems with the scale that need to be corrected.
Is C2 Electronic Calibration as accurate as calibration with test weights?
Theoretically, test weights should provide an accurate calibration within the quality of the scale installation. However, calibration conditions are often less than ideal. Many vessels lack the space needed to place enough test weights on them to get an accurate calibration. Distributing the weights equally on the vessel may also be impossible. Some vessels are mounted in areas offering limited accessibility, while others have weight capacities far in excess of available test weights. These real world issues often cause calibration errors.
With C2, these considerations are no longer an issue. Each individual load sensor has its performance characteristics stored on an internal chip. These characteristics are measured on National Institute of Standards and Technology (NIST) traceable test devices and electronically recorded when the sensor is manufactured. The C2 system uses these parameters, the instruments’ characteristics and a reference point to calibrate the scale system. The sensor’s C2 characteristics are also backed up on the cloud where they are easily accessible.
C2 reduces downtime for repairs and time waiting for test weights. It eliminates test weight related injuries and ends material substitution headaches, including contamination and waste disposal issues. C2 is a standard feature on Hardy load sensors, weigh modules, and weight and rate controllers.
A. The thick (0.060") outer jacket protects signal leads from minor nicks and cuts and helps keep moisture and contaminants out. The vinyl material used is flexible for conduit bends and slides more easily in long conduit runs. Additionally, this material resists many corrosive substances.
B. 36 gauge braided tinned copper shield provides better than 85% coverage and tight braid angles to reduce the chance of outside electrical noise reaching the signal leads. Unlike other process measurements, incremental changes in weight correspond to signal changes typically in the range of 0.0000001 volts (0.1 micro volt). Without proper shielding, common plant electrical noise can cause fluctuation and incorrect weight readings.
C.A mylar barrier reduces the chance of moisture reaching the signal leads should the cable be nicked. Moisture between signal leads increases the capacitance between signals and results in cross coupling of voltages and incorrect weight readings.
D. The 22 gauge wire is stranded for reliability in bends and is color-coded for easy installation.
E. Two wires make up a twisted pair to reduce capacitance for C2 signals and provide a constant cable impedance.
The Hardy Process Toolbox is a set of productivity tools that support industrial weighing functions. Each tool saves time, increases accuracy, improves efficiency, or reduces risk in process weighing applications, including WAVERSAVER® to eliminate vibration, C2® electronic calibration, and Integrated Technician® to name just a few.
Hardy C2® cable supports the following Hardy Process Toolbox functions when coupled with a Hardy Instrument, Load Cells and a Hardy Junction Box.
C2® (or eCAL) Electronic Calibration
The Hardy C2® (or eCAL as it is known in China) core feature provides quick and easy electronic calibration of a weighing system without the need for heavy test weights.
INTEGRATED TECHNICIAN® Operator Diagnostics
Hardy's INTEGRATED TECHNICIAN (IT) core feature helps you troubleshoot your weighing system and diagnose problems from the front of the instrument or via the PLC. These tests display system weights, voltages, and pass/fail displays to help isolate a problem to the instrument, cabling, or sensors, helping to reduce maintenance costs.