STR series 11 2-Stage Servovalve Rated flows up to 12 l/m Features Maximum operating pressure 5 bar Electric feedback at main stage spool ISO 441-5-5-4 mounting pattern (NG1) Internal or pilot supply & return (4, 5 or 6 port) Suitable for -way or 4-way applications Low hysteresis & zero point drift High spool drive forces Spool in bushing design Dry torque motor with mechanical feedback Long life Sapphire Technology Star Hydraulics Limited Severn Drive Tewkesbury usiness Park Tewkesbury Gloucestershire GL2 8SF England (UK) www.star-hydraulics.co.uk ST-116.1-En
enefits and Features Sapphire ball in slot design Incorporated into Star designs since 1988 Many billions of cycles per service life Increased spool life due to spool rotation Ultra low coefficient of friction sapphire to steel Feedback mechanism unhindered by spool rotation Extended warranties available Safety Flame proof Intrinsic safety Class, Div & Zone coverage Mechanical failsafe Double & triple coil redundancy Quality Independant audit process is our commitment on quality Focus on customer needs and expectations Delivery schedules on time Continual improvements on products and services Maintaining design and manufacturing integrity Custom spool lap & bushing port geometries Zero overlap Overlap (closed center) underlap (open center) Dual gain symmetric gain Special projects Compact servo designs Special interfaces Modular components Sapphire flow Ensuring first stage stability Precisely matched flow properties Long life in extreme environments Sealing materials Nitrile Fluorocarbon (Viton) Ethylene-Propylene Fluorosilicone Special connectors MIL-C-515 MIL-DTL-8999 Conduit style male/female Hermetic
Technical data Hydraulic Nominal flow ratings [±1%] at 7 bar Dp 5, 9, 12 l/m Operating pressure (max) Ports P, C1, C2, X R, Y Seal material NR, FPM 5 bar 15 bar Fluid viscosity range (recommended) Fluid type 1 to 1 mm 2 /s (cst) Mineral oil to ISO 11158, DIN 51524 or equivalent MIL-H-566 Kerosene Water glycols others on request Filter rating (recommended) Pressure line eta 1 = 2 (1 µm abs), non by-pass & indicator Off-line eta 2 = 1 (2 µm abs) Fluid cleanliness ISO 446: 1999 minimum 16/ 14/ 11 recommended 15/ 1/ 1 Operational parameters Hysteresis.5% Threshold.1% Null shift T 4 C 1.5% Internal leakage 14 bar supply (.5% overlap) 2. l/m Load pressure difference 1% input % of supply pressure can be as high as 1% Response time -1% rated spool stroke 5, 9 l/m 2 ms 12 l/m ms Mounting pattern Mounting position ISO 441-5-5-4 with X & Y port ny, fixed or movable Weight std unit 4.4 kg Design protection EN 6529 IP 65 Shipping protection Vibration Shock Seal material options Sealed base plate g all axis, 5 Hz to 2, Hz g all axis NR, FPM Temperature range -2 to 8 C
Technical data - Electrical details Factory set options are as follows Pin Function Dual rail power supply (code 'D') C Supply Supply Supply / signal ground +15 Vdc (+14.5 Vdc min +18 Vdc max) Vdc (-14.5 Vdc min Vdc max) V D Input rated command (differential) See order codes for V or I options E F Inverse Main stage spool position O/P See order codes for V or I options PE Protective earth Pin C D E F PE Function Supply Supply / signal ground n.c Input rated command (differential) Inverse Main stage spool position O/P Protective earth Single rail power supply (code 'S') +24 V (+2 Vdc min +28 Vdc max) V See order codes for V or I options See order codes for V or I options Power supply Current (m) < 1 each rail (typically 5) Ripple (mv p-p) < 1 Command signal Phasing Voltage input Current input +4 +2 m When input at pin D = +ve with respect to pin E causes flow from P»,»T impedance 1 Mohm impedance 2 ohm at +12 m spool is in centred position Spool position output Voltage output Current output Output impedance <1 ohm, minimum receiver impedance 1 kohm Output impedance > 1k ohm, minimum receiver impedance ohm, maximum receiver impedance 4 ohm Protection Reverse Polarity Over-voltage Indefinite bsolute max +/- 2 V DC
Internal leakage (l/m) % Supply pressure % Rated flow Flow rate Q (l/m) Technical data Output Polarity (per std wiring) Flow for 1% input as a function of valve pressure drop 1 75 P»,»T 5 25 1-25 -5-75 P»,»T -1-1 -75-5 -25 25 5 75 1 % Rated input signal 1 1 7 1 Valve pressure drop p (bar) Typical Load Pressure Difference v Input Signal The flow tolerance for standard servovalves is ±1% of the rated flow at 1% rated input signal. 1 8 6 4 2-2 -4-8 Rated Signal [In] is the specified input voltage or current of either polarity to produce rated flow. Rated input does not include null bias values. Rated flow corresponds to the flow at rated input at 1 bar or 7 bar, with no load, therefore in 4-way valves there will be a pressure drop of 5 bar or 5 bar respectively across each land. Load pressure difference versus input signal indicates typical differential pressure gain between ports C1 () and C2 () for standard lap spools. Negative and positive overlap change this characteristic signifcantly. Internal leakage comprises of tare first stage and laminar leakage between spool and sleeve. With critical lap conditions in 4-way designs the leakage peaks through the null region. -1-5 -4 - -2-1 1 2 4 5 % Rated input signal Internal Leakage v Input Signal 5 4 2 1-1 -8-4 -2 2 4 6 8 1 % Rated input signal
mplitude Ratio (d) mplitude Ratio (d) mplitude Ratio (d) mplitude Ratio (d) mplitude Ratio (d) mplitude Ratio (d) Technical data Freq. Resp. at 25% Un or In, 21 bar, Code 11x-5 & 9S Freq. Resp. at 9% Un or In, 21 bar, Code 11x-5 & 9S - - 1 1 1 1 1 1 1 1 Freq. Resp. at 25% Un or In, 21 bar, Code 11xS Freq. Resp. at 9% Un or In, 21 bar, Code 11xS - - 1 1 1 1 1 1 1 1 Frequency Response at 1% In 92HF H, pilot C Frequency Response at 1% In 92HF H, pilot C - -. 1 1 1 1 1 1 1 1
Order code 1 1 Pilot configuration Description Code Special order code X internal, Y internal Factory defined X external, Y internal 2 X external, Y external 7 may be reconfigured in field see page 7 for details Connector style Code Description 6 6-Way (MS12-14SP) Rated flow 7 6+PE (MS12-14S-7P) Qn (1 bar) Qn (7 bar) Code 19 l/m 5 l/m 5 X Special 5 l/m 9 l/m 9 45 l/m 12 l/m 12 Lap condition Code Description % to 1% positive, linear (std) Response level X Special Description Code Standard S High response H De-energized control spool position Code Description 1% P»,» T 1% P»,» T X Not defined Operating pressure (main stage) Description Code 21 bar 21 Seal material 28 bar 28 Code Description 5 bar 5 N NR V FPM (Viton) Connector direction Electronics Description Code Code Rated signal I/P Spool O/P 1 ±1 Vdc ±1 Vdc 2 ±1 m ±1 m 4 ±1 Vdc +4 2 m 5 ±1 m +4 2 m Code Supply voltage D Dual rail +15// Vdc (pin outs,, C) S Single rail +24 Vdc (pin outs, )
11 series INSTLLTION DETILS STR Mounting screws Skt head cap screws M6 x 6-1.9 ISO 4762 Null adjust (Electrical) Pilot stage configuration Remove button headed screw, insert potentiometer driver & rotate to desired null point Internal pilot supply when 'GS1' installed at valve port 'X' External pilot supply when 'GS1' installed at 'Loc-1' Internal pilot return when 'GS2' installed at valve port 'Y' External pilot return when 'GS2' installed at 'Loc-2' Porting details Interface seals Replacement filter P,,, T, T2 ports 9. 15.7 1.4 X, Y ports. 18.7 1.4 Ports P,,, T, T2 - ID 12.4 x 1.78 O-Ring Ports X, Y - ID 15.6 x 1.78 O-Ring PN: SRS2916. Requires 8 /F hex key Loc-2 Loc-1 72 42 DETIL 181 DETIL F PE 14 1 E 91 D C 66 GS2 GS1 15 min. W WRNING do not attempt to remove plugs or filter when valve is pressurized F1 F2 Mounting interface conforms to ISO 441-5-5-4 P T T2 X Y F1 F2 F F4 size 1 1 1 1 1 M6 M6 M6 M6 x 27 16.7 7..2 5.8-8 62 54 54 y 6. 21.4 21.4 2.5 2.5 11 11 46 46 75 min. X T P Y T2 Surface flat within.1 / 1 : finish better than.8 μm F4 F