Introduction to feedback modulo servo 150Introduction The feedback ms150 modluo servo system 150 intended for experimental use by students to a starting on studies of close loop system and who may be more concerned with obtaining a general qualitative graph close loop techniques than precise analytic investigation. This makes it idiolly suited to the needs of the trainee technician engineer and craft students and irt is such students that the basic assignments in this manual. Equipment: THE MS150 MODULO modulo system comprising a dedicated power supply a servo amplifier,two motor units ,a reduction gaer,techo unit and a number of transducers and modules Varios combinations of these itoms form ,DC,AC over hybrid servo system as required DESCRIPTION: OP AMP UNIT: A general purpose amp with facilities for multiple inputs and various feed back arrangements uses includes summation to produce operating error for close loop system , addition of extra time const. to demonstrate instability. ATTENUATOR UNIT: Twin calliberated potentiometers mounted in one case ,available for gain and techo feedback control. PRE_AMP UNIT: It has two input channels and a push pull out put for direct drive of the servo amp. SERVO AMP: Operates the motors to which it may be connected via a 12 way socket. POWER SUPPLY: Input tapings are 115V and 230V, 50 /60 Hz, 40VA. Output 24V DC, 2A, unregulated connects directly to the servo amp via an 8way socket. DC MOTOR: The modulator section has band width of 60 Hz. experimental filters may be connected. In the demodulate condition the bandwidth is about 5 Hz with the filtered connected. SIMULATED REALY: Converts the DC MS150 into a relay type control system with two step and three step control characteristics. SYNCHRO TRANSMITTER: . The motor shaft is extended for direct mounting of the magnetic break and inertia disks. mounted and fitted with caliberated position indicating lines. INPUT OUTPUT POTENTIOMETERS : Semi precision. LOADING UNIT: Complete with break disk{thin} and inertia disk {thik}.1 to 100 Hz in three decades SYNCHRO TRANSFORMER: It is coupled directly to the motor low speed output shaft by the feed back coupler provided.with an operating range of 0. The output unit carries a rear extension shaft for coupling directly to the reduction gear techo unit.This is a permanent magnet motor. servo –type potentiometers . SAMPLE AND HOLD UNIT: Consists of zero orderhold circuits and compatible pulse generator. with the filter off. MOD/DEMODE UNIT: It has an adjustable phase shift network covering 0 to nearly 180 degree to correct the refrnce input. The motor shaft is extended for direct mounting of the magnetic brake and inertia discs. AC MOTOR: A two phase AC induction motor connected via 12 way plug servo amplifier. .the center frequency can be tuned to 50 or 60 Hz carrier. Complete with fully accessories. The maximum speed is 80rpm. it has two facilities 1: phase adjusting control channel 2: an active FILTER AC COMPENSATION UNIT: It represent the apair of complex poles in the denominator and a pair of complex zeros in the numerator.CONTAINS AN AUXILIARY DRIVE MOTOR WHOSE SPEED IS CONTROL BY A POOTENTIOMETER. AC PRE AMPLIFIER UNIT: This unit preceeds the servo amplifier SA150D. The modulator circuit transform a DC tacho generator signal into an AC tacho generator signal. 270mm.270mm.red 6 leads 4mm plug.grey 4 leads 4mm plug. ANCILLARY ITEMS 150Z COMPRISES: • • • • • • • • 1 Plastic coated speed steel base plate 8 leads 4mm plug .REDUCTION GEAR TACHO UNIT: This contains 30:1 speed reduction gear box and a DC tacho generator driven from the high speed input shaft. 570mm yellow .270mm. grey 7 leads 4mm plug.green 6 leads 4mm plug270mm. PID UNIT: This is a propotional + integral+ derivative control unit for use with MS150 or other feed back control systems using DC electrical signals.yellow 4 leads 4mm plug.orange 2 leads 4mm plug.165mm.165mm. grey 6 leads 4mm plug.570mm.570mm.5mm UNIT SUPPLIED WITH EACH EQUIPMENT F F F G H H H J K K K K F K L L L L L R S T U V M R R S S T T U U V V W X W X X W X X Y Z Z Z Z Z MODULAR SERVO SYSTEMS Comlete MS 150-3 AC/DCsyst em MS 150-2 DC system MS150 AC system MS150A MODULAR DIGITAL SERVO SYSTEM DS 150-1 comprisin DS153plus A A A A B B B B C C C C D D D D D E E E E E CONVERSION SETS: FROM DC TO AC/DC HYBRID.3core 2spanners DE OJ1/4’’*3/16”BS 1 allen key 1.1 50 RST FROM R S T U V W .• • • • • 2 leads 4mm plug.green 4 leads 4mm plug. A function generator range of . G M J Y Z .cahnnel amplifiers are desirable though not absolutely essential.05-20 Hz producing sine.preferably with storage facility.HYBRID TO FULLY AC. This should be a two cahnnel DC coupled oscillosciope . Display facility. Identical X.150U VW FROM DC TO FULLY AC.square and triangle waveforms.150 RST/UVW FROM AC TO COMPLET E AC/ DC R S T U V W C F H ADDITIONAL UNITS SIMULATE D RELAY UNIT SR150G SAMPLE & HOLD UNIT SH150M DIFFERENT IAL SYNCHRO DS150J PID UNIT PID150Y 150Z=BAS E UNIT & ACCESSOR IES ANCILLARY EQUIOPMENT: In order to drive the maximum benefit from ht e moudular servo system the use of the following ancillary equipmemnt is essential.and Y. The main power supply for the servo amplifier unit and the motor unit are fed through the cables terminating in plugs fitted to board the motor and the servo amplifier unit. and a square wve at same frequency and in quadrature with ramp is applied to Y-axis.g.axis . OU150A AU150B PA 150 C SA150D PS150E DCM150F IP150H OP150K LU150L GT150X DISPLAY METHOD: OP AMP UNIT ATTANUATOR UNIT PRE AMP UNIT SERVO AMP POWER SUPPLY DC MOTOR INPUT POTENTIOMETER OUTPUT POTENTIOMETER LOADING UNIT REDUCTION GEAR TACHO UNIT If a ramp i/p is used to drive an oscilloscope X. When ever the brake is in use it should be positioned as follows: Set the brake scale to 10 and position the pbrake on the base plate so that the disc runs freely between the magnets. Both power supplies and servo amplifier are fitted with 4mm sockets from which ±15 DC supplies can drawn to operate all other units of the system. The components of MS150 modulo servo may be abbreviated in the text for convenience e. . the tacho generatior voltage has been used directly as a measure of speed. The speed reduction between high speed and low speed shaft is 30:1.DC volt meter 30-0-30V HOW TO USE MS 150: In order to reduce the number of instructions for each assignment the following general information is given: Each of the units of this equipment is fitted with a magnetic base and can be attached to the baseboard in any desired position. a display in the following figure. Trough out the assignment indications rather than actual speeds are required. . If the system response to the square wvae is displayed . The actual phase shift = (a/b)*90° And the amplitude can be measured from C.Y will be eual to the peak-to-peak value of ht e i/p and X will be equal in time to haolf the period of the ramp. If a sine wave is inphase with the ramp is applied to the system and there is a phase shift between i/p and o/p the following display will occur. PRACTICAL CONTENTS: The practical in assignment 1 provides some introduction to the 33-002 before more detailed investigations are carried out.ANALOGUE SERVO FUNDAMENTAL TRAINER The following practicals are included in this assignment (1) Initial mechanical and analogue unit check. (3) To display the speed response of the motor. . (2) To display the waveform. 1. you should • • • Have some experience using an electric motor Have some experience of handling electronic circuits Know how to use an oscilloscope PRELIMINARY PROCEDURE: The power supply should be connected by 4-mm plug leads to the +15 V .5A Oscilloscope. +5V. storage or long persistence. FIGURE: ANALOGUE UNIT ..5A: +5V dc.the mechanical unit and analogue unit. Be familiar with two of the sub-systems . unit Power supply ±15 V DC.EQUIPPMENTS: QTY 1 1 1 1 DESIGNATION 33-110 33-100 DESCRIPTION Analogue unit Mech. preferably with X-Y facility OBJECTIVES: When we have completed assignments we will • • Realize that 33-002 equuipment comprises sub systems which may be combibned various ways to make control system. KNIOWLEDGE LEVEL: Before you have strat this assignment. 0V and -15V sockets at the back of mechanical unit. The output shaft speed display should show. Hold the switch left and the motor should run anti-clockwise with approximately the same speed. connect its output to the nechanical unit.will not be used with the analogue unit.1: (1) INITIAL MECHANICAL AND ANALOGUE UNIT CHECK.speed and output tracks . Set the brake fully upwords. there must be slight movement when the supply is actually switched.the digital facilities in the mechaniocal unit .0. Switch the power supply ON. This test indicates that the ±15V supplies are operating . The analogue unit should not be connected. . With the power supply switched off .Initially examine the mechanical and analog units without making any connections and identify all items mentioned in the figures 1 and 2. PRACTICAL 3. Hold the motor check switch to the right and the motor should run clockwise and the output speed display should indicate 15-25 RPM. The motor should remain stationary.00 this indicates that the 5V supply is operating. Raise the brake fully. Overall the test indicate that the system is working correctly. Connect the analogyue to the mechanical unit via 34-way cable. Switch the power ON. Rotating the power amplifier zero adjustment should enabvle the motor to be driven in both directuions upto about the same speed as before. These test indicates that power supply and mechanical unit are operating correctly. . Zero the amplifier to stopp the motor.ow down.hold the check switch to one side and gradually lower the brake to maximum the motor should sl. Switch the power off.