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Table of Contents
Related Manuals for Flintec EA250
Summary of Contents for Flintec EA250
- Page 1 EA250 Analogue Amplifier User Manual flintec.com...
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Page 2: Table Of Contents
Remote Shunt Calibration ......................18 Chapter 6 Troubleshooting ......................19 Chapter 7 Product Care ....................... 21 Chapter 8 Glossary ........................22 Chapter 9 Specifications for EA250 Load Cell Amplifiers ..............25 CE Approvals..........................26 Warranty ..........................26 Figure 9.1 Connection Details ......................27 Flintec EA250 User Manual ea250-e-aa-man-en-1.0.0... -
Page 3: Chapter 1 Introduction To Ea250
9-36V DC. See Figure2.3 for details. The ISS1224 can only be fitted to the EA250/DC as it occupies the same space as the mains transformer in the EA250/AC. The EA250/AC however, is isolated when AC powered by virtue of its mains transformer. -
Page 4: Chapter 2 Installing The Ea250
See Specification details in Chapter 10 for details of Environmental Approvals. Carefully remove the EA250/AC unit from its packing. Check that the unit is complete and undamaged. The EA250 units can operated in any industrial environment providing the following limits are not exceeded Operating Temperature -10 ºC to +50 ºC... -
Page 5: Cabling
(This diagram is also provided inside the lid). Figure 2.3 IS1224 Module Connections To accommodate automotive installations, the EA250 can be fitted with an IS1224 module enabling it to be powered from 9 to 36V DC. This module also has the advantage of electrically isolating the DC power supply from the measurement electronics which minimises errors and instability due to earth loops in the system. - Page 6 Strain Input is the Signal from the transducer. The Ref 5V/2.5V is generated internally and used for calibration The cable connecting the sensor to the EA250 should be shielded. This typical cable data is provided for information only. The cable should have 2 x twin twisted cables. Ideally with each pair individually shielded and with an overall shield.
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Page 7: Output Connections
Figure 2.5 Output Connections In ‘Sink’ mode the positive end of the load is connected to the internal +15V supply on the EA250 and the negative end is connected to the EA250 output. The current through the load is ‘sunk’ by the EA250 towards ground (0V). -
Page 8: Chapter 3 Switch Settings
Low pass filtering is switched into operation by setting SW4/6 ‘ON’↑ and SW4/7 ‘OFF’↓. Reverse these settings to bypass the filter. It should be noted that either one of these switches MUST be on but not BOTH Flintec EA250 User Manual ea250-e-aa-man-en-1.0.0... -
Page 9: Output Filter Settings -Switch 3
↓ ↓ ** Note: A SECONDARY low pass filter, with a cut off frequency of 800Hz, can be switched into the EA250 input by fitting a link to JP3 (see Figure 3.2) Important: Low pass filtering is switched into operation by setting SW4/6 ‘ON’↑ and SW4/7 ‘OFF’↓. -
Page 10: Output Current Mode And Input Filter Settings - Jumpers Jp1, Jp2 & Jp3
50Hz ↑ ↑ ↑ ↑ ↑ ↑ ↑ ↑ Output Current Mode and Input Filter Settings – Jumpers JP1, JP2 & JP3 Figure 3.2 Refer to Figure 2.5 for details of wiring connections to J1. Flintec EA250 User Manual ea250-e-aa-man-en-1.0.0... -
Page 11: Span (Gain) Setting Switch Sw1
When using 5V Excitation (SW4 switch 8 = OFF), divide the transducer's mV/V output by two and set SW1 to the nearest setting shown in table 3.6 above e.g. for 2.5mV/V with 5V excitation choose the 1.2mV/V setting Flintec EA250 User Manual ea250-e-aa-man-en-1.0.0... -
Page 12: Shunt Calibration Switch Sw1/8
Shunt Calibration Switch SW1/8 SW1/8 connects a 120k 50ppm surface mount resistor across the ‘+Excitation’ and ‘+ Input’ terminals of the EA250. This shunts one arm of the connected load cell to produce a known change in output which can be used for calibration or checking the integrity of the load cell and associated wiring. -
Page 13: Zero (Offset) Setting Switch Sw2
'OFF '. Switch settings 3 to 8 are ADDITIVE. The offset value of each switch is added to give a total offset of 78%. Fine adjustment is provided by potentiometer P2. Flintec EA250 User Manual ea250-e-aa-man-en-1.0.0... -
Page 14: Chapter 4 Calibration
Chapter 4 Calibration The EA250 provides the excitation supply and signal conditioning to cater for a wide range of strain gauges, load cells, pressure transducers or torque transducers. Output Select the analogue output range as detailed in Chapter 3, Figure 3.1, Tables 3.1 & 3.2 by means of SW4. - Page 15 The EA250 can be calibrated with the transducer connected, provided that two calibration points can be implemented, e.g. by applying known weights or forces. If this is not possible, a stable mV source or load cell simulator can be used provided that the precise sensitivity (mV/V) and full range output (kg) of the transducer is known.
- Page 16 If this is the case, note the reading, e.g. 0.5V, apply the high calibration conditions and trim P1 for the required change in output, i.e. Trim the output for 0.5 + 7.5 = 8V. Flintec EA250 User Manual ea250-e-aa-man-en-1.0.0...
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Page 17: Chapter 5 The Ea250Bcm Bridge Completion Module
Chapter 5 The EA250BCM Bridge Completion Module The EA250BCM is a retro-fit PCB which facilitates connecting a half or quarter-bridge strain gauge to the EA250. Screw terminal connections accept a wide range of bridge completion resistor types and enable on-site installation without soldering equipment. -
Page 18: Shunt Calibration
An additional feature of the EA250BCM allows the user to perform a ‘Shunt Calibration’ (shunt cal) test to check the integrity of the strain gauge(s), wiring and EA250 calibration. This involves temporarily connecting a relatively high value resistor between the positive output of the bridge to either the positive or negative excitation connections. -
Page 19: Remote Shunt Calibration
In addition, ‘Remote Shunt Cal’ can be performed by means of a N.O. 24V DC relay fitted to the module. The relay supply can be situated some distance from the EA250 and even be connected in parallel to several EA250s in a multiple installation enabling them to be shunt cal’d simultaneously. -
Page 20: Chapter 6 Troubleshooting
Refer to tutorial on the calibration set-up f) Check the calibration. Incorrect setting of the calibration span switches is the most common cause of high output - particularly when associated with ± Voltage outputs. Flintec EA250 User Manual ea250-e-aa-man-en-1.0.0... - Page 21 If the potentiometer does not alter the output the unit must be repaired – remove from service. It is always wise to check a known good EA250 against the problem installation before rejecting the suspect EA250. Flintec EA250 User Manual...
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Page 22: Chapter 7 Product Care
Please refer to ‘Customer Repair Service Procedure’ document – contact your supplier for a copy. In the unlikely event you have problems with the EA250 module we would advise that you take the following precautions:- •... -
Page 23: Chapter 8 Glossary
The impedance presented to the output terminals of a transducer by the associated external circuitry. Load cell The load cell is one of a series of Strain Gauge sensors that the EA250 input is designed to accept. (Torque Sensor, Pressure & temperature transducers). - Page 24 Strain Gauge Amplifier - in that it conditions (alters) the input signal from a load cell to an electrical output Single card assembly The EA250 has only the one Printed Circuit Board assembly on which all the components are mounted. The assembly is then mounted inside an environmentally rugged enclosure.
- Page 25 The span of the EA250 can be offset from zero (zero suppressed) such that neither limit of the span will be zero. For example, an EA250 which measures a load of a 100kg span from 400kg to 500kg° is said to have 400kG zero suppression.
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Page 26: Chapter 9 Specifications For Ea250 Load Cell Amplifiers
Chapter 9 Specifications for EA250 Load Cell Amplifiers Parameter Typical Units Power supply (EA250/AC):- (110/230Vac) 50-60Hz 110/230 V AC Power supply dc: - V DC (See note 1) Power supply current dc: - (depends on loading) Bridge excitation (10V range) 9.75... -
Page 27: Ce Approvals
If the Flintec product you purchase appears to have a defect in material or workmanship or fails during normal use within the period, please contact your Distributor, who will assist you in resolving the problem. If it is necessary to return the product to Flintec please include a note stating name, company, address, phone number and a detailed description of the problem. - Page 28 Figure 9.1 Connection Details In the interests of continued product development, Flintec reserves the right to alter product specifications without prior notice. Flintec EA250 User Manual ea250-e-aa-man-en-1.0.0...