Electronic amplifier for the control of proportional valves without position control Model VT 3024, Series 3X H/A 4149/94 VT X

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1 RA /0.98 Electronic amplifier for the control of proportional valves without position control Model T 3024, Series 3X RA /2.9 The amplifier T X is suitable for the control of pilot operated proportional directional valves (WRZ, Series X and older) and direct operated pressure valves (DBEP, 3DREP, Series 1X) without position control. H/A 4149/94 Characteristics: Differential input Step function generator Ramp function generator Two pulsed current output stages Polarity protection for the voltage supply Note: When supplied the amplifiers have a ramp time of 5 s. (Setting of ramp time of 1 s see page 5) T X Card Holder: CH 32C-1X, see RA T X/32, see RA Output curve 800 Solenoid A Solenoid B Output current in ma Command value in % /

2 RA /0.98 Technical data (For application outside these parameters, please consult us!) Operating voltage 1 ) DC 24 DC; + 0 %; 5 % Function range Upper limit value (momentary value) DC (t) max 39 Lower limit value (momentary value) DC (t) min 22 Power consumption I < 1 A (with loading current) Fuse I S 2.5 A time lag, M5 x 20 Inputs Command value 5 e ± (Reference potential is M0) Command value input (differential input) e 0 to ±10 ; R e = 100 kω Relay Data Nominal voltage Operating voltage DC Threshold voltage 1.8 Return voltage 2.4 Coil resistance R 2150 Ω Ramp time (Setting range) t 30 ms to approx. 1 s or 5 s Controlled voltage ± 9 ± 1 %; 50 ma. externally loadable Solenoid current I max 800 ma; R (20) = 19.5 Ω Pilot current I 20 ma ± 25 % Pulse frequency of output stages f 170 Hz ± 10 % Test points Command value w ± ; R i = 5 kω Actual current value, I B A, B 0 to 800 m 0 to 800 ma Type of connection 32-pin terminal strip, DIN 41 12, type D Card dimensions Euro-Card 100 x 10 mm, DIN Frontplate dimensions Height 3 U, 5.0 in (128.4 mm) Width soldering side 1 HP, 0.20 in (5.08 mm) 1 division Width component side 7 HP 7 divisions Perm. operating temperature t F (0 50 C) to DIN/IEC 8-2, T1, T2, T14 and T30 2 ) Storage temperature t F ( C) 2 ) Disturbance resistance Class 3 to DIN/DE 843 T2 and T4 2 ) Mechanical loadability to DIN/IEC 8-2, T, T24 and T27 2 ) Weight m 0.29 lbs (0.13 kg) 1 ) To guarantee the maximum solenoid current for the 19.5 Ω-solenoid in the highest solenoid temperature range, the operating voltage must be at least 28 DC! 2 ) For further details please consult us! 2/

3 Positive command value controls solenoid B Negative command value controls solenoid A Differential input Command value 5 ± (Command 1 to 4 are not applicable) ±10 Command value Reference potential/ GND Measuring Zero (M0) is raised by 9 compared to 0 operating voltage! + 9 M0 9 X1 14c 14a 1a 1c 18a 20c 20a 2c 1 2 F t K5 3 J5, J 4 7 = Command value at w 0 to + for solenoid A 0 to for solenoid B Current at Current I B at I B F A MT w F µf R7 R8 F I B I I X1 30a 24a 22a 28a 32c 32a + DC 2a 0 Solenoid A Solenoid B Operating voltage Block circuit diagram / terminal connection T X Call-up Ramp Off 18c K5 Call-up voltage relay (±24 ) 28c F = on frontplate 3/ K5 = Call-up Ramp Off R7 = Pilot current solenoid A R8 = Pilot current solenoid B t = Ramp time 1 Differential input 2; 5 Summation 3 Ramp generator 4 Step function Current amplifier with pulse generator 7 Power supply RA /0.98

4 RA /0.98 Functional description The command value is a differential input (0 to ± 10 ) 2 ). When using external electronics, this differential input must be used. When switching off or on the command value voltage it must be taken care that both signal lines are either separated from or connected to the input. External command value potentiometer 5 K 5 K 5 K 20c 20a 2a 2c 20a 2a 20c 2c 2a Input + 9 M0 Input 9 Control "Solenoid B" Control "Solenoid A" Control "Solenoid A+B" The command value 5 can be used for testing function with the control voltages ± 9 of the power supply [7] or via an external command value potentiometer. For the input "command value 5" ± is ± 100% 1 ). The command values are summed with the correct value and sign before they are connected further [2]. The ramp generator [3] produces a ramp output signal from the step input signal. The time constant can be set with the potentiometer "t". The ramp time given refers to a command value step of 100% and can be set via jumpers - approximately 1 s or 5 s. If a command value smaller than 100% is made, the ramp time is shortened appropriately. M0 Input External ramp time potentiometer and ramp "Off" 500 K 14a 14c 2a 14a 14c Ramp "controllable" time: min. = 0 Ω time: max. = 500 kω Ramp "On/Off" Note: When using an external ramp time potentiometer the internal potentiometer for the ramp time must be set at maximum. The maximum ramp time decreases, because the resistance of the external potentiometer is connected in parallel to the internal potentiometer! By switching the relay K5 with 24 DC (smoothed) or closing an external bridge, shown above, the ramp time is set to its minimum value (approx. 30 ms). The output signal of the ramp generator [3] goes parallel to the summation [5] and the step function generator [4]. The step function generator produces with command value voltages of > ± 1 % a polarity-dependent constant jump signal which is added to the output signal of the ramp generator. This jump function causes the rapid travelling across the overlapping area of the valve. The output signal of the summation [5] is the command value and is led to the two current output stages [] and to the test point "w" on the frontplate of the card. A voltage of at the command value test point corresponds to a command value of 100 %. A positive command value signal at the input of the amplifier controls the output stage for solenoid B, and a negative signal controls the output stage for solenoid A. When the command value signal is smaller than ± 1 % (step function still ineffective) a pilot current of 20 ma flows through both solenoids. The actual values of the currents through both solenoids can be measured separately at the sockets (solenoid A) and I B (solenoid B). Here a current of 800 ma corresponds to a voltage of 800 ma. 1 ) = Reference potential for the command value is M0 (measuring zero). 2 ) = Reference potential for the differential input should be grounded to 0 at the source end. [ ] = Allocation in block circuit diagram 4/

5 Display / setting elements T X RA /0.98 max. ramp time approx. 1 sec or 5 sec H11 - yellow LED display "Power on" H12 - green LED display "No fault" H11 H12 J J5 X1 t - Ramp time w - Command current value solenoid I B - Actual current value solenoid B - Actual current value solenoid A t w I B F1 2.5 A MT Meaning of jumpers on the card for settings (Label on the back of the frontplate) ramp time Jx = bridge bridge plugged in 5 s J5 J Jx = open bridge open 1 s J5 J = delivery state Delivery condition Ramp time Note: The loss of unused jumpers can be avoided by plugging the jumpers into only one pin. Project / maintenance instructions / additional information The amplifier card may only be unplugged or plugged in when power is off! Do not use fly-back diodes or LED s when connecting the solenoids! Measurments at the card may only be carried out with instruments R i > 100 kω! Measuring zero (M0) is increased by + 9 compared to 0 - operating voltage and is not potentially separated - i.e. ( 9 ) controlled voltage 0 operating voltage. Therefore, the measuring zero (M0) must not be connected with 0 operating voltage! For switching of the command values used relays with dry contacts (small voltages, small currents)! For switching of the card relay only use contacts with a load capacity of approx. 40, 50 ma! When using external control the control voltage may have a residual ripple factor of a maximum of 10 %! Always shield command value lines; shield to be connected to 0 operating voltage on the card side, leave other side open! Recommendation: Also shield solenoid lines! For solenoid lines of up to 150 ft (50 m) length use stranded 1 AWG (LiYCY 1.5 mm 2 ). For longer length please consult us! The distance to aerial lines, radio sources and radar equipment must at least be 3 ft (1 m)! Solenoid and signal lines must not be laid near power lines! Because of loading current of the smoothing capacitor on the card, fuse must be time lag! If switching the differential input, both sides must be switched simultaneously (use DPDT dry contacts). When using the differential input, an isolated analog common should be grounded to 0 from the card s power source, at one point on the source end. 5/

6 RA /0.98 Ordering code T X/ * Amplifier for proportional valves without position control Series 30 to 39 (Technical data and terminal connections unchanged) = 3X Further details in clear text Unit dimensions: dimensions in inches (millimeters) H11 H12 3U 5.0 (128.4) 3.94 (100) 3.50 (89) t w I B 0.59 (15) T HP 1.59 (40.3) 0.28 (7).50 (15) 7.32 (18) 0.08 (2) 0.28 (7) / Mannesmann Rexroth Corporation Rexroth Hydraulics Div., Industrial, 2315 City Line Road, Bethlehem, PA Tel. (10) Fax: (10) Rexroth Hydraulics Div., Mobile, 1700 Old Mansfield Road, Wooster, OH Tel. (330) Fax: (330) All rights reserved Subject to revision Printed in U.S.A.