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Application of V260 Series Inverters on Straight Wire-Drawing Machines

Abstract:

Metal products are quite crucial in metallurgical industry, but this industry is rather weak in China as hindered by obsolete mechanical and electrical equipments. In the respect of metal processing, the straight wire-drawing machine is a kind of usual, yet relative advanced and promising wire drawing machines. In the past what is used is often DC generator-motor unit (F-D system). Nowadays, with advancement of process technologies and popularization of inverters, inverters are increasingly widely used in straight wire-drawing machines. In addition, the use of PLC enables such functions as setting of drawing varieties, operation automation, control over production process, real-time closed-loop control and automatic metering.

Keywords: Straight Wire-Drawing Machine,Sunfar,inverter

I. Foreword
  Metal products are quite crucial in metallurgical industry, but this industry is rather weak in China as hindered by obsolete mechanical and electrical equipments. In the respect of metal processing, the straight wire-drawing machine is a kind of usual, yet relative advanced and promising wire drawing machines. In the past what is used is often DC generator-motor unit (F-D system). Nowadays, with advancement of process technologies and popularization of inverters, inverters are increasingly widely used in straight wire-drawing machines. In addition, the use of PLC enables such functions as setting of drawing varieties, operation automation, control over production process, real-time closed-loop control and automatic metering.
  With the use of inverter speed-adjusting system, the straight wire-drawing machine features advanced technology and significant energy saving, with the speed adjusting range being 30:1 at the normal working time. In addition, it can provide over 1.5 times of rated torque at 5% rated revolution.
  This article illustrates the application process and effect of inverter control by taking example of a certain straight wire-drawing machine production site for producing steel wires.

II. Process introduction and requirements


 

                                                 system control flow chart

       The equipment is mainly used to draw and pull steel wires. 6.5mm enter-wires become 2.43 mm out-wires after

subjecting to processing of 6 drawing dies. The highest drawing speed is 8 m/s. For the drawing part, there are

totally 6 drums with diameter of 550mm. In-between adjacent drums is installed with cylinder oscillating bars for

detecting position. The position of swing arms can be detected with a displacement sensor. When wires are draw tightly, the pressure imposed by wires on the swing arm’s cylinder forces the swing arm to move forward, hence accelerating the machine in front and achieving tension control between each level. The rewind motor adopts a taper support that can slide freely. Over the whole process, the rewind diameter does not change. The rewind motor is kept constant with the liner speed of the main wire-drawing machine depending on adjustment conducted by tuning rollers. Main requirements are as below:
1.Each set has the function of job FWD and jog REV.
2.Have front linkage (the first set has no front linkage) and the rear linkage (rewinding has no rear linkage).
3.Mode hopping function (including main wire-drawing machine) and automatic calculation of system frequency ratio according to mode hopping conditions.
4.System operating speed 8 m/s at maximum.
5.Automatic metering and weighting, and automatic stop when preset meter and weight is reached.
6.Stable acceleration and deceleration without high fluctuation.
7.Stable operation of the system, and circuit-break detection alarm and stop function

 

III. System solutions and commissioning
1.System composition

Name  Specifications  Qty
PLC FX2N-128MR-1 1
Contact screen  Weilun 10” 1
D/A module  FX2N-4DA 2
Inverter  V560-4T0300 6
Inverter  V560-4T0185 1
Switch power supply    1
Button    Several
Relay    Several

 

2.System solution
       According to principle that straight wire-drawing machines have equivalent volume, the system can make calculation in the PLC of main preset speed for each level of N-level driven wire-drawing machines, main wire-drawing machines and rewind machines based on the modules with human-machine interface and mechanical commission ratio, which will be then transmitted to AI1 port of the inverter respectively in ladder type way of D/A modules of PLC. The inverter make micro-adjustment through signals fed back by the swing bar so as to realizing constant tension between each level of the system. PLC is integrated internally with front linkage, rear linkage, wire-breaking detection, metering and weighting, etc.

 

3.Logical requirements of system action
       There are only 3 logical relationships between the first machine and rewind motor. Aside jog forward and jog

reverse, etc, the first machine also has the rear linkage function and the rewind motor has the front linkage

function. From the second-level driven wire-drawing machine to the main wire-drawing machine, there are 4 logical relations, which is respectively jog forward, jog reverse, front linkage and rear linkage. Take examples as below:
3# jog forward:3#closed forward jog terminal

3# jog reverse:3#closed reverse jog terminal

3# front linkage: 1# run, 2# run, 3# run, and 3# is the main machine (the speed setting is by PLC analog AI2,

without swing bar feedback)
3# rear linkage: 3#run, 4#run, 5#run, 6#run (main machine), 7# run

4.Mode hopping function
       Except for the rewind motor, any one set or several sets of machines of the system may be subject to mode hopping(but generally at least one set for the main wire-drawing machine or N-level driven wire-drawing machine is reserved for the main motor).

5.Commissioning parameters

Setting of N-level driven wire-drawing machine
F0.1.16=13                  The frequency set value is the total of two channel setting values
F0.1.19=0.15                 The set coefficient of channel 2 is 15%
F0.1.23=4.00                 FWD jog frequency is 4HZ
F0.1.24=4.00                 REV jog frequency is 4HZ
F0.2.25=9                    The setting source of channel 1 is analog AI1 setting
F0.2.26=23                   The setting source of channel 2 is process PID output
F0.3.33=1                    The control mode is terminal setting
F1.0.03=2.00                  The acceleration time is 2S
F1.0.04=1.80                  The deceleration time is 1.8S
F1.0.09=5.00                  Jog acceleration time is 5S
F1.0.10=5.00 Jog deceleration time is 5S
F3.0.00=7 DI1 is running signal
F3.0.01=5 DI2 is FWD jog signal
F3.0.02=6 DI3 is REV jog signal
F3.0.03=14 DI4 is EMS signal
F3.0.05=22 DI6 is process PID input signal
F3.0.12=6 DO1 is fault output
F3.0.21=27 Wire-breaking detection function starting detection
F3.0.27=17 Wire-breaking detection
F3.0.30=95.0 Wire-breaking detection
F9.0.31=95.0 Wire-breaking detection
F5.3.28=0007 The frequency setting channel enjoys the highest priority
F7.0.00=2002 Process PID is terminal input
F7.0.08=60.0 PID setting value
F7.0.10=1 PID feedback is AI2
F7.0.17=0.55 P value of process PID
F7.0.18=20.00 I value of process PID
F7.0.21=0010 Output bipolarity of process PID
F7.0.22=0.0 PID static deviation is 0

 

Parameter setting for main wire-drawing machine
F0.1.23=2.00 FWD jog frequency is 4HZ
F0.1.24=2.00 REV jog frequency is 4HZ
F0.2.25=9 Frequency setting source is AI1 setting
F0.3.33=1 The control mode is terminal setting
F1.0.03=35.00 The acceleration time is 35S
F1.0.04=35.00 The deceleration time is 35S
F1.0.09=5.00 Jog acceleration time is 5S
F1.0.10=5.00 Jog deceleration time is 5S
F3.0.00=7 DI1 is running signal
F3.0.01=5 DI2 is FWD jog signal
F3.0.02=6 DI3 is REV jog signal
F3.0.03=14 DI4 is EMS signal
F3.12=6 DO1 is fault output

 

Parameter setting for the rewind motor
F0.1.16=13                  The frequency set value is the total of two channel setting values
F0.1.19=0.15                 The set coefficient of channel 2 is 15%
F0.1.23=4.00                 FWD jog frequency is 4HZ
F0.1.24=4.00                 REV jog frequency is 4HZ
F0.2.25=9                    The setting source of channel 1 is analog AI1 setting
F0.2.26=23                   The setting source of channel 2 is process PID output
F0.3.33=1                    The control mode is terminal setting
F1.0.03=2.00                  The acceleration time is 2S
F1.0.04=1.80                  The deceleration time is 1.8S
F1.0.09=5.00                  Jog acceleration time is 5S
F1.0.10=5.00 Jog deceleration time is 5S
F3.0.00=7 DI1 is running signal
F3.0.01=5 DI2 is FWD jog signals
F3.0.02=6 DI3 is REV jog signals
F3.0.03=14 DI4 is EMS signals
F3.0.05=22 DI6 is process PID input signals
F3.0.12=6 DO1 is fault output
F3.0.21=27 Wire-breaking detection function starting detectio
F3.0.27=17 Wire-breaking detection
F3.0.30=95.0 Wire-breaking detection
F9.0.31=95.0 Wire-breaking detection
F5.3.28=0007 The frequency setting channel enjoys the highest priority
F7.0.00=2001 Process PID is terminal input
F7.0.08=60.0 PID setting value
F7.0.10=1 PID feedback is AI2
F7.0.17=0.55 P value of process PID
F7.0.18=20.00 I value of process PID
F7.0.21=0010 Output bipolarity of process PID
F7.0.22=0.0 PID static deviation is 0

 

6.Commissioning steps
Follow below wiring diagram (part of diagram) to connect wires.

              wirng diagram 1                                                    wiring diagram 2

Connect wires according to the system wiring diagram, and check especially the mains cord connection of PLC and the inverter. Power on after check.
(1) Self-study of motor parameters
After setting [F2.0.00] –[F2.0.04] according to the motor’ s actual parameters, set [F2.2.53]=1 to start static

self-study.
(2) After study of motor parameters, set parameters according to above commissioning parameters;
Access commissioning after completing preparation of above-mentioned commissioning.
(3) Adjust the maximum value and minimum value of cylinder swing bar sensor. The larger the range is, the higher the adjustment precision and the better the adjustment effect. Adjustment is monitored through D1.0.04. after adjustment, respectively modify AI2 corresponding minimum value [F4.0.02] and maximum value [F4.0.03].
(4) After calibration of cylinder swing bar and before threading, check if the braking device and belt pulley of

each set is well installed for the jogging of the first set to the last set.
(5) Start threading and commissioning. Conduct commissioning according to the threading sequence from manual mode to linage mode and from low speed to high speed.
(6) The commissioning process is focused on PID limited ratio and P value and I value of PID. According to previous experience, I value should be higher than the acceleration and deceleration time of N-level driven wire-drawing machine and rewind motor and less than the acceleration and deceleration time of the main wire-drawing machine. In case wires getting loss in the previous wire-drawing machine during the process of threading and linkage, it indicates that the PID amplitude limiting value is too low. The value of [F0.0.19] should be revised. Generally,the amplitude limit of the system is within 10%-20%. Excessive high P value may lead to large swinging amplitude of the swinging bar, hence causing ventilation. P value is generally between 0.3 and 0.8, and should be adjusted from small to large.  
(7) After threading at low speed, test the front linkage and rear linkage functions.
(8) After completion of logical tests, start low-speed starting and then gradually increase speed to make

adjustment. After several times of start and stop, the commissioning of the entire system is done.

 

V. Commissioning effect and conclusions
  By adopting the drive with a SUNFAR V260 high-performance vector inverter, the system can work stably at high speed with smooth threading, start and stop after parameter optimization, hence dramatically reducing wire breaking faults. Compared with DC drive system, the efficiency and electricity saving is greatly increased. In addition, the electrical apparatuses of this system are concisely configured with clear logistics, convenient for fault detection.