3-1 TO FIX THE WGA-120A ....................28 3-1-1 To mount the WGA-120A onto the panel ..............28 3-1-2 To mount the WGA-120A onto the DIN rail ..............29 3-2 TO CONNECT POWER SUPPLY ..................30 3-3 TO CONNECT TRANSDUCERS ..................32 3-4 TO CONNECT TRANSDUCERS IN PARALLEL .............
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4. OPERATION PROCEDURES ....................38 4-1 TO TURN ON THE POWER .................... 40 4-2 TO ADJUST THE ZERO BALANCE ................40 4-3 TO ADJUST THE SPAN ....................41 4-3-1 By the actual load calibration ..................41 4-3-2 By the CAL ........................ 44 4-4 CORRECTION REQUIRED WHEN AN EXTENSION CABLE WAS USED ....
Also, keep the manual within easy reach so that you can refer to it whenever necessary. For safe use of the WGA-120A, do not forget to read the "Safety Precautions" prior to use. Kyowa Electronic Instruments Co., Ltd. assumes no liability for any damage resulting from the user's...
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For safety operation of the WGA-120A, the following symbol marks are used in the Instruction Manual. Indicates “PROTECTIVE GROUND TERMINAL.” Be sure to connect the GND terminal to the ground. For safety operation of the WGA-120A, the following symbol marks are used in the Instruction Manual.
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△ ! WARNING Power supply To prevent a fire hazard, ensure that the power supply voltage specified for the WGA-120A matches the local line voltage before turning ON the power. The power supply voltages are described in the following. DC model: 10.5 to 15 VDC, power dissipation 3.5 W or less...
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Confirmation of protective functions To prevent electric shock hazards, when any trouble occurs in protective functions including the GND terminal and a fuse, do not to operate the product. Furthermore, before operating the product, always check whether error exists or not in protective functions. Fuse When the pilot lamp does not light up, the fuse may be blown.
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Storage and usage in gases Do not use/store the WGA-120A in inflammable gases, explosive gases, or vapor. Using the WGA-120A under the above environment is too risky. External connection To prevent electric shock hazards, be sure to connect the GND terminal to the ground before connecting the object to be measured and external control circuit to the product.
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Power supply Use the WGA-120A within the specified power voltage. The WGA-120A has 4 types: 10.5 to 15 VDC, 100 VAC, 200 VAC, 240 VAC. (We are able to manufacture 110 VAC model and 220 VAC model.) PRECAUTIONS FOR USE...
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Do not disassemble or remodel the WGA-120A. It may cause electric shock hazards or damage the WGA-120A. This warranty does not cover any damaged or defective parts that results from disassembling or remodeling. The output signal (voltage/current) when the transducer cable is broken.
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Using them exceeding the years specified according to each part type (useful life) may affect the characteristics of the WGA-120A, resulting in a malfunction or a failure. You need to replace parts with a regular preventive maintenance schedule.
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Preventive maintenance and replacement parts are a cost-effective way of keeping the performance and extending the service life of the WGA-120A. Regardless of the replacement parts, the WGA-120A itself gradually deteriorates with age. Before the expected service life is reached, consider replacing the...
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Precautions on CE marking Be sure to mount the WGA-120A on the control panel, etc. Before turning ON the power, make sure the WGA-120A is covered to avoid contact with hands. The WGA-120A connection, jumper changing, BAL/CAL switch operation, adjuster operations, and fuse replacement should be executed by experts in electrical work.
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Function ZERO balance The WGA-120A has manual balance model and auto balance model (external contact points are also available). The WGA-120A is able to change excitation voltage, output signal (voltage/current), sensitivity, calibration value (CAL), and frequency response.
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Model The WGA-120A series has 8 models. Customers are required to purchase the power cable applied for your power supply specifications. Model Balance adjustment Power supply specs WGA-120A-00 Manual WGA-120A-01 Manual 100 VAC WGA-120A-02 Manual 200 VAC WGA-120A-03 Manual 240 VAC...
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Pilot lamp Lights up in green while the power is supplied to the WGA-120A. When the WGA-120A is slave unit in the synchronous operation, the pilot lamp lights up in orange. (See “3-5 TO USE STRAIN GAGES.”) ZERO coarse adjuster(ZM) Coarse adjusts the ZERO of the output signal (voltage/current).
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(See “4-5 AUTO BALANCE ADJUSTMENT.”) Power supply input terminal Power supply terminal. Power supply varies with WGA-120A models. Carefully read the Specifications before connecting the power supply. Protective ground terminal GND terminal. Be sure to connect the product to the ground before turning ON the power.
2. INITIAL SETTINGS This section describes how to select the bridge excitation voltage, output signal (voltage/current), sensitivity, CAL, frequency response by using jumpers on the built-in PCBs. Be sure to read this section prior to use. Factory-configured settings Bridge excitation voltage: 1 Vrms Input: 5mV/V (=5000µV/V), Output: 10 V Output signal:...
Remove screws (on b both sides). ② Remove 4 flat t head screws (M2.6) locat ted on the WGA-120A side panels. R Remove the cover. ③ Change the jum mpers (JP1 to JP8) on the PCB to your desired settings.
① Disconnect the e power cable. Remove screws (on bot th sides). ② Remove 4 flat t head screws (M2.6) locat ted on the WGA-120A side panel. ③ Remove the A Auto balance PCB (40×30 m mm) from the WGA-120A m main PCB.
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NOTE Do not change jumpers under dusty environment or humid place. Do not take procedures other than what is described on the 2-1 and 2-2. Or, it may cause trouble. Do not touch the other parts or do not remove screws other than the specified screws.
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3 to 6 3 to 4 3 to 4 0.25mV/V 2 to 3 0.05mV/V 1 to 2 Frequency response 10Hz 1 to 2 30Hz 3 to 6 100Hz 2 to 5 500Hz 1 to 4 mpers in the WGA-120A -20-...
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le 2-1 Jumper settings 1 Setting items Setting contents Jumper settings Jumper setting figure Bridge 1 Vrms 1, between 2 to 4 excitation Applicable 7, between 1 to 2 voltage bridge resistance 8, between 1 to 2 87.5 to 1000 ohm 2 Vrms 1, between 1 to 2 (Be sure to set...
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le 2-2 Jumper settings 2 Setting items Setting contents Jumper settings Jumper setting figure Output Voltage 2, between 1 to 2 Current 2, between 2 to 3 Sensitivity ×10000 3, between 1 to 4 4, between 1 to 3 (Auto balance model: The JP3 ×4000 3, between 2 to 5...
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le 2-3 Jumper settings 3 Setting items Setting contents Jumper settings Jumper setting figure 0.25mV/V 5, between 2 to 3 0.05mV/V 5, between 1 to 2 Frequency 10 Hz 6, between 1 to 2 response 30 Hz 6, between 3 to 6 100 Hz 6, between 2 to 5 500 Hz...
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Table 2-4 Available range to be output the full scale value (voltage: ±10 V, current: 20 mA) Input range (mV/V) Sensitive Bridge excitation SPAN range switch voltage (Vrms) × 1 × 0.4 ±5 ±12.5 × 2000 ±2.5 ±6.25 ±1 ±2.5 ±2.5 ±6.25 ×...
2-3 EXAMPLE OF CHANGING JUMPE [For using Kyow a's load cell LMR-S-5KN SA2] ① Find the test d data sheet of the LMR-S-5K KNSA2. Rated capacity Rated output 1293 µV/V (=1.2 293mV/V) Calibration constant 0.003868kN/1 µ µV/V Input & output resistance 351.6 6 ohm -25-...
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When the bridge resistance (input & output resistances on the test data sheet) is 175 ohm or more, the WGA-120A is able to use any excitation voltage. Since the input & output resistances of the LMR-S-5KNSA2 is 351.6 ohm, the WGA-120A is able to use any excitation voltage. However, the recommended excitation voltage of the LMR-S-5KNSA2, described on the instruction manual, is 1 to 2 V.
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④ Set the sensitivity. Since the excitation voltage is 2Vrms in the ②, to output the full scale value, the sensitivity should be ×4000. Set the sensitivity ×4000. (“Sensitivity: ×4000” JP3: Between 2 to 5, JP4: Between 2 to 4) ⑤...
3. CONNECTION The WGA-120A does not include cables since the WGA-120A is an amplifier, designed to be used in a system. The WGA-120A is able to mount by using 2 holes (φ4.5) on the fitting metal. The WGA-120A is able to mount on the DIN rail by using Kyowa's DIN rail mounting plate (optional: EDP-70).
DI IN rail by mounting the D DIN rail mounting plate (ED DP-70, optional) onto the e WGA-120A rear panel. T The WGA-120A has holes s (described as follows) on n its rear panel for fixing th he DIN rail mounting plat te.
(1) For 100 VAC model/200 VAC model/240 VAC model The terminal block has terminal cover. Before connecting the AC power cable to the Power supply input terminal, remove the terminal cover. Use Kyowa's AC power cable (optional). AC power cable for 100 VAC: P-23...
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(2) For DC power supply model Use cables having the solderless terminal for copper wire 1.25-3 (conforming to JIS C 2805) or equivalent. Connect the power supply, 10.5 to 15 V (200 mA or more), to the Power supply input terminal. The withstand voltage of the cable should be the power supply voltage or more.
Transducer input terminal 3-4 TO CONNE CT TRANSDUCERS IN N PARALLEL The WGA-120A connects up to 4 transduc ers (bridge resistance: 350 0 ohm) in parallel. Transducers shou uld be the same model and d same capacity. At this tim me, the bridge resistance is s 87.5 ohm.
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Securely connect the transducers to the terminal block. Or, it may cause troubles. The WGA-120A amplifies (×2000 to ×10000) the minute electrical signals to output the output signal (±10V or 4 to 20mA). The WGA-120A also amplifies (×2000 to ×10000) small noises.
3-5 TO USE STR RAIN GAGES To measure multi iple strains at the same tim me by using strain gages an nd multiple WGA-120A un nits, be sure to synchroni ize the oscillator signals. T The synchronous operation n prevents beat, due to the...
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MEMO Beat phenom menon The WGA-1 120A uses the oscillator sig gnals, generated inside the e WGA-120A, for operatio ons. Suppose stra ain gages are bonded to th e same object to be measu ured. When measuring data a by...
3-6 TO CONNECT THE AUTO BALANCE CONTROL INPUT TERMINAL The Auto balance control input terminal (AZ and COM) on the terminal block is designed to execute the auto balance adjustment. Use a contact point (switch or relay). Terminals for executing the auto balance adjustment are as follows. Terminal block External Internal...
OUT + : Positive side of the voltage output/current output(±10 V or 4 to 20 mA) OUT - : Negative side of the voltage output/current output (the same potential as the COM) The WGA-120A is able to change the output signal (voltage/current) by using the internal jumpers. For details, see “2. INITIAL SETTINGS”.
4. OPERATION PROCEDURES Make sure all wires are correctly connected. Turn ON the power. The pilot lamp lights up. Preheat the WGA-120A approximately 30 minutes. Initialize the load or weight of the transducer. (Normally, no load is applied or weight is 0.)
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When the fine-adjustment is required, fine-adjust the output signal (voltage) to be 0 V (current: 4mA), by turning the ZERO fine adjuster. Sensitivity adjustment Actual load calibration based on the CAL Apply the actual (known) load or weight to When the Actual Load Calibration is not the transducers.
4-1 TO TURN ON THE POWER Before turning ON the power, make sure the WGA-120A is correctly connected. Although the WGA-120A will be in operating state immediately after turning ON the power, we recommend you to preheat the WGA-120A 30 minutes for stable measurements.
The above procedures indicate how to adjust the ZERO by using the output signal (voltage). The WGA-120A is also able to adjust the ZERO by using the output signal (current). The output signals (current: 4 to 20 mA) move in tandem with the output signals (voltage: 0 to +10).
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Then, with the weight (1kN) applied to the load cell, adjust the output signal to be 1.00 V or 10.00 V for reading the weight directly. Suppose the WGA-120A outputs 1.00 V when applying the weight (1kN). When the WGA-120A outputs 0.80V, the applied weight is 0.8kN.
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[Example 2] Actual load calibration 2 Load cell Rated capacity: 1kN Assume that 5 V output signal is required when 1kN is loaded. When applying the weight (0.8kN), the output signal (voltage, V) is as follows. 0.8×5 Output = = 4 (V) First, with the no load applied, turn the Sensitivity adjuster all the way to the right to execute the balance adjustment.
4-3-2 By the CAL Make sure no load is applied to the transducers (weight: 0). Adjust the value on the digital voltmeter, connected to the Output terminal (OUT+ and OUT-), by turning the Sensitivity adjuster with the BAL/CAL switch pushed down. The CAL varies with the bridge resistances to be connected.
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MEMO The CALs are based on the 350-ohm bridge. The CALs are based on the parallel resistance method. The WGA-120A connects the parallel resistors (described in the above table) between the G terminal and R terminal while the BAL/CAL switch is pushed down.
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When using the other bridge resistances, described in the table 4-1, calculate the CAL (mV/V) by using the following formula. CAL = × 10 (mV/V) (Formula 4-1) 4(Rc+Rg) Rg: Bridge resistance (ohm) Rc: Parallel resistors CAL 0.25mV/V: Substitute 350×10 (ohm) CAL 0.05mV/V: Substitute 1750×10 (ohm)
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[Example 1] How to calculate the CAL CAL: 0.25mV/V, Bridge resistance: 500 ohm The actual CAL to be used is as follows. CAL = × 10 4(Rc+Rg) × 10 = 0.357 (mV/V) 4 (350 × 10 + 500) -47-...
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Load cell Rated capacity: Bridge resistance: 1000 ohm Calibration constant: 0.0005005kN/1μV/V (= 0.5005kN/1mV/V) *Calibration constant: Unique value described on the test data sheet CAL of the WGA-120A 0.25mV/V (350-ohm bridge), that is, 0.712mV/V (1000-ohm bridge, see the table 4-1) -48-...
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The above procedures indicate how to adjust the ZERO by using the output signal (voltage). The WGA-120A is also able to adjust the ZERO by using the output signal (current). The output signals (current: 4 to 20 mA) move in tandem with the output signals (voltage: 0 to +10).
4-4 CORRECTION REQUIRED WHEN AN EXTENSION CABLE WAS USED When using an extension cable, the measured value contains an error due to an extension cable. The longer an extension cable is used, the larger a measurement error grows. In order to remove this error, multiply the measured value by a correction value.
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× 10 (Formula 4-2) L: Cable length (m) ρ: Cable resistivity (ohm・m) S: Cable cross section(mm When using Kyowa's extension cables (N-81 to 85, N-100), ρ is 1.7×10 (ohm・m). ② Calculate the correction value. Correction value = r × A +1...
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Then, with an extension cable connected, execute the sensitivity adjustment by the CAL to output 4 V when the CAL is 0.25mV/V. After the sensitivity adjustment, the WGA-120A outputs 5.00 V. To calculate the true output, remove the cable extension errors as follows.
After executing the auto balance adjustment, the WGA-120A outputs the output signal (voltage) 0V. The WGA-120A outputs the output signal (current) 4mA. Even if the WGA-120A is turned OFF, the state of the output signal (voltage/current) are maintained to have the same state before the power OFF.
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NOTE Take care no chattering generates on the slope (negative) and slope (positive) of the contact point signal. -54-...
5. SPECIFICATIONS 5-1 SPECIFICATIONS Applicable Transducer Strain gage transducers Number of Measuring Channels Applicable Bridge Resistance 87.5 to 1000 ohm (Up to four 350-ohm transducers can be connected in parallel. Bridge excitation voltage is limited to 2 or 1 Vrms for transducers with bridge resistance less than 175 ohm) Bridge Excitation Voltage 5 Vrms, 2 Vrms, or 1 Vrms, Square wave...
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Zero Adjustment Range Within ±1.5 mV/V, manual balance or auto balance by selecting model. Sensitivity Adjustment Range ×2000, ×4000, ×10000 (Switchable by changing internal jumper connection) Adjustable between ×0.4 and ×1.0 by the trimmer. Calibration Calibration by the parallel resistance method 0.25mV/V or 0.05mV/V at 350-ohm bridge resistance (Switchable by changing internal jumper connection) Frequency Response...
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Stability Temperature Zero: Within ±0.2μV /℃ Sensitivity: Within ±0.05%/℃ Time Zero: Within ±0.5μV Sensitivity: Within ±0.2%/8H [Conditions] Sensitivity: ×10000, ×1.0(Adjustment by the trimmer), Bridge resistance: 120 ohm, Bridge excitation voltage: 2 Vrms Applicable Standards EMC standards EN61326-1 (Class A) Safety standards EN61010-1 EN61010-2-030 (Installation category II,Pollution degree 2, Measureing...
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Power Supply Voltage/Power Consumption 10.5 to 15 VDC, 3.5W or less 90 to 110 VAC, 6.5VA or less 180 to 220 VAC, 6.5VA or less 216 to 264 VAC, 6.5VA or less (Varies with the models) Dimensions 44 (W) × 90 (H) ×80 (D) mm (excluding protrusions) Weight DC power supply model: Approx.
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Transducer's outp p ut and output signal (volt age/current) -59-...
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Available range to be output the full scale value (voltage: ±10 V, current: 20 mA) Input range (mV/V) Sensitive Bridge excitation SPAN range switch voltage (Vrms) × 1 × 0.4 ±5 ±12.5 × 2000 ±2.5 ±6.25 ±1 ±2.5 ±2.5 ±6.25 ×...
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