Created on 03/11/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 1 of 2
MODEL
LOECZ
Pilot-to-close, spring biased closed, unbalanced poppet logic element with
metering notches and position switch
SERIES 2 / CAPACITY: 45 L/min. / CAVITY: T-2A
These unbalanced, pilot-to-close logic valves are 2-way switching elements that are spring biased closed. Pressure
at either work port 1 or 2 will oppose the spring and tend to open the valve while pressure at port 3 will tend to
close it. The force generated by the pressure at port 3, plus the spring force, must be greater than the sum of the
forces generated by the pressures at ports 1 and 2 for the valve to remain closed.
This valve incorporates a position switch to provide confirmation that the valve is closed.
TECHNICAL DATA
Maximum Operating Pressure 350 bar
Maximum Valve Leakage at 110 SUS (24 cSt) 0,07 cc/min.
Pilot Volume Displacement 1,1 cc
Pilot Passage into Valve 0,9 mm
Area Ratio, A3 to A1 1.8:1
Area Ratio, A3 to A2 2.25:1
Transition leakage at 110 SUS (24 cSt) 30 cc/min.@70 bar
Seal kit - Cartridge Buna: 990-202-007
Seal kit - Cartridge Polyurethane: 990-002-002
Seal kit - Cartridge Viton: 990-202-006
SWITCH SPECIFICATIONS
Supply Voltage 20-30 VDC
Reverse Polarity Protection Yes
Maximum Output Load ≤ 400 mA, Duty Ratio 100%
Short Circuit Protection Yes, Load Short Unlimited
Turn On Time ≤ 25 ms
Hysteresis ≤ .002 in.
Operating Temperature Range -25 to 80 °C
Thermal Shift - 0 to 80 °C ≤ ± 0,1 mm
EMC DIN EN 61000-6-1/2/3/4
Vibration ≥ 50g, 0-500 impulses/sec
Shock >50 g, 1ms
snhy.com/
LOECZ
Created on 03/11/2016
c
2016 Sun Hydraulics Corporation See www.sunhydraulics.com for detailed product information 2 of 2
Connector M12 X 1 (4) Pin
Connector Environment Rating IP65
(D)NOMINAL CONTROL PRESSURE
D 50 psi (3,5 bar)
(N)SEAL MATERIAL
N Buna-N
V Viton
TECHNICAL FEATURES
This valve has metering notches in the poppet to reduce hydraulic shock during valve opening and closing.
The position switch in this valve provides confirmation that the valve is closed.
These valves have positive seals between port 2 and the pilot area.
This cartridge is supplied as a sealed, factory set unit and is not field serviceable. Any tampering will violate the product warranty.
When torquing this cartridge into its cavity, a crow's foot wrench or similar will be required since the position switch precludes the use of a deep socket wrench.
Because these valves are unbalanced, operation is pressure dependent. Opening and closing of the poppet are functions of the force balances on three areas: Port
1 = 100%, Port 2 = 80%, and the Pilot Area = 180%.
These valves are pressure responsive at all ports, therefore it is essential to consider all aspects of system operation through a complete cycle. Pressure changes
at any one port may cause a valve to switch from a closed to an open position, or vice versa. All possible pressure changes in the complete circuit must be
considered to assure a safe, functional system design.
All ports will accept 5000 psi (350 bar).
Position switch is CE approved.
An optional protective cover, with mounting hardware included, may be ordered separately. See kit number: 991-043.
Incorporates the Sun floating style construction to minimize the possibility of internal parts binding due to excessive installation torque and/or cavity/cartridge
machining variations.
PERFORMANCE CURVES
RELATED MODELS
LOEC Pilot-to-close, spring biased closed, unbalanced poppet logic element with metering notches
Model Code Example: LOECZDNCONFIGURATION OPTIONS