ELECTRIC CARTRIDGES ELECTRO-PROPORTIONAL VALVES

ELECTRIC CARTRIDGES ELECTRO-PROPORTIONAL VALVES 6. 9

ELECTRO-PROPORTIONAL VALVES ELECTRIC CARTRIDGES ELECTRO-PROPORTIONAL VALVES In the follow of this chapter, NEM presents the electro-proportional flow control cartridges, the flow regulator cartidges and the pressure regulator cartridges. The flow control valves, equipped with proportional solenoid, provide the adjustment of the efflux area by imposing energy to the electric coils. The proportional cartridges are seat in standard cavities and can be connected to pressure compensators in order to obtain flow regulator circuits. Below, a glossary of technical terms, which have been used in this catalogue, has been reported. Current: electrons flow produced by voltage across a coil. whose power is proportional to the crossing current and the number of coils. Common abbreviation is I. No load current: power consumed by the proportional controller when no coil output is available. Threshold current (or polarization): point where increasing input current causes a flow or pressure variation Maximum working current: is the point where input current no longer results into a flow pressure variation. I min - I max: is the minimum and maximum control current fed to the solenoid of the proportional cartridge. Hysteresis: is the measure of the output current difference between increasing and decreasing current in the solenoid. Example: when current is increasing you need ma current to produce a L/min flow. When current is decreasing,you need ma current to get the same flow. So there is a 6 ma difference in input current to achieve gpm flow depending on whether current is increasing or decreasing. If I max = 6mA, and Imin = ma the total input difference is = ma. Hysteresis=(6/) =.%. Pulse with modulation (PWM): amount method used to vary the average current induced in a coil by a squere wave of fixed frequency and variable time ratios. time ON = time OFF % Induced current % time on % Induced current % time on % Induced current ON OFF 6 7 Proportional controller or amplifier: electronic device converting a low - power input signal into an output signal capable of operating the valve. This output signal can be modified to include PWM ramping or dither. Ramping: a system for adjustment of output current variation of a proportional control. Compensator: hydraulic device combined to proportional control valves to provide fixed outlet flow when pressure change. Voltage: current flow potential in an electric circuit. It is measured in units called volts (and is sometimes abbreviated V). Generally, higher voltage will induce a higher current. 6 6.

ELECTRO-PROPORTIONAL VALVES ELECTRIC CARTRIDGES ELECTRIC CONTROL REQUIREMENTS NEM spa offers a range of electro proportional controls equipped with and Vcc coils. On going test indicates that a current from to Hz significantly improves the valve performance, as against operation with straight Vcc. The graphs on the side show how the addition of PWM noticeably reduces hysteresis. This feature is available from virtually all standard controls manufacturers at low cost. For valves,hysteresis is represented by a double tracking curve where as the lower and upper track show decreasing and increasing current respectively. These valves are not designed for rapid operation rates. Please consult the factory if relatively fast valve response is required. One way of enhancing operation rates is to add a control function for (I min - I max) adjustment. This function will allow control across the full range. Again, this feature is widely available on commercial products. Many commercially available controllers also include ramping control. TYPICAL HYSTERESIS RAMP SLOPE CONTROL Vcc current Vac current Current (A) Pressure/Flow Current Pressure/Flow Current ramp on time ramp off time l min adjustment l max adjustment Time (S) Pressure/Flow Current 6. 6

. Cartridge SAE WAY Normally Closed SPOOL VALVE, ELECTRO-PROPORTIONAL flow CONTROL Flow................................ l/min Max working pressure in :............... bar Application limits with p max from to...... bar Leakage.......................... cc/min Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque................... Nm Weight (with coil)........................, Kg Cavity...................... C page Body......................... 7 page 9 Coil (to be ordered separately)...... 9 page Ø,,,,,,,6,7,,9(V),,,6,,,,,6,(V) Graph flow/current with p from to of 7 bar Hex.7 7/- UNF-A 6, Ø, Pressure drop with energized coil 7 % Q.max % Q.max % Q.max % Q.max Flow range No emergency Push pin Handknob 6 6.

. Cartridge SAE WAY Normally Closed SPOOL VALVE, ELECTRO-PROPORTIONAL flow CONTROL Flow................................ 7 l/min Max working pressure in :............... bar Application limits with p max from to...... bar Leakage.......................... cc/min Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque................... Nm Weight (with coil)........................,6 Kg Cavity...................... C page Coil (to be ordered separately)...... 9 page 9 Ø 9 7 6,,,,,,6,7,,9 (V),,,6,,,,,6, (V) Graph flow/current with p from to of bar Hex. 6 -/6"- UNFA 6 Ø, 6 6 Pressure drop from to 7 Qmax 7 l/min Qmax l/min Flow range No emergency Push pin Handknob 6. 6

. Cartridge SAE WAY Normally closed POPPET VALVE, ELECTRO-PROPORTIONAL flow CONTROL Flow................................ l/min Max working pressure in :............... bar Leakage.........................., cc/min Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque.................. Nm Weight (with coil)........................, Kg Cavity...................... C page Body......................... 7 page 9 Coil (to be ordered separately)...... 9 page Ø,,,,6,7,,9 (V),6,,,,,6, (V) Graph flow/current with p from to Hex.7, 7/- UNF-A Ø, Pressure drop from to 7 % Q.max % Q.max Flow range Push pin Push Button Push and Twist Handknob 6 6.

WAY Normally Open SPOOL VALVE, ELECTRO-proportional flow CONTROL. Cartridge SAE Flow................................ l/min Max working pressure in ::............. bar Application limits with p max from to...... bar Leakage.......................... cc/min Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque................... Nm Weight (with coil)........................,6 Kg Cavity...................... C page Body......................... 7 page 9 Coil (to be ordered separately)...... 9 page Ø,,,,,,,6,7 (V),,,6,,,, (V) Graph flow/current with p from to of 7 bar Hex.7 6 7/- UNF-A Ø 7, 6 Ø, Pressure drop with de-energized coil 7 % Q.max % Q.max % Q.max % Q.max Flow range No emergency Push pin Handknob 6. 6

Cartridge SAE WAY normally closed spool valve, ELECTRO-proportional FLOW CONTROL Flow................................ l/min Max working pressure in ::............. bar Application limits with p max from to...... bar Leakage.......................... cc/min Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque................... Nm Weight (with coil)........................,6 Kg Cavity...................... C page Body......................... 7 page 9 Coil (to be ordered separately)...... 9 page Ø Scheme Scheme,,,,,,,6,7,,9 (V),,,6,,,,,6, (V) Graph flow/current with p from to of 7 bar Hex.7 6 Ø, 7/- UNF-A Ø 7, 6 Pressure drop with de-energized coil Hydraulic scheme 7 % Q.max % Q.max % Q.max % Q.max Flow range No emergency Push pin Handknob 66 6.

Cartridge SAE WAY normally closed spool valve, ELECTRO-proportional FLOW CONTROL Flow................................ 7 l/min Max working pressure.................... bar Max working pressure in................. bar Application limits with p max from to...... bar Leakage.......................... cc/min Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque.................. Nm Weight (with coil)........................,7 Kg Cavity...................... C page Body......................... 7 page 97 Coil (to be ordered separately)...... 9 page Ø 6 Scheme Scheme 7 9 Hex.,,,,6,7,,9 (V),6,,,,,6, (V) Graph flow/current with p from to of 7 bar Graph with p from to of bar 69, Ø, -/6"- UNFA Ø, 7 6 6 7 Pressure drop with energized coil 7 Hydraulic scheme 7 % Q.max % Q.max 7% Q.max Flow range No emergency Push pin Handknob 6. 67

7 Cartridge SAE WAY spool valve, ELECTRO-proportional FLOW control Maximum flow......................... l/min Max working pressure in ::............. bar Max working pressure in................. bar Application limits with p max from to /.... bar Leakage.......................... cc/min Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque.................. Nm Weight (with coil).........................,9 Kg Cavity...................... C page 6 Body......................... 7 page 9 Coil (to be ordered separately)...... 9 page Ø S Scheme Scheme Scheme S,,,,6,7,,9 (V),6,,,,,6, (V) Graph flow/current with p from to / of 7 bar 6 Hex.7 7/- UNF-A Ø 9 Ø 7, Ø, 7 Pressure drop with energized coil from to / Hydraulic scheme Qmax 9 l/min Qmax l/min Qmax l/min Flow range No emergency Safety lever 6 6.

. Cartridge SAE ELECTRO-proportional pressure relief valve, direct acting Flow................................. l/min Max working pressure in................. bar Max working pressure in.................. bar Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque................... Nm Weight (with coil)........................,6 Kg Cavity...................... C page Body......................... 7 page 6 Coil (to be ordered separately)...... 9 page Ø 9, 6,,,,,,6,7,,9 (V),,,6,,,,,6, (V) Hex. / -6 UNF-A 6 7,,,,, Ø,7 SETTING RANGE Min - Max [bar] 7 Push pin Handknob 6. 69

6. Cartridge SAE ELECTRO-proportional pressure relief valve, pilot operated Flow................................ 6 l/min Max working pressure.................... bar Max current at Vcc...................mA Max current at Vcc....................9mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque.................. Nm Weight (with coil)........................, Kg Cavity...................... C page Body......................... 7 page 9 Coil (to be ordered separately)...... 9 page Ø 6,,,,,,6,7,,9 (V),,,6,,,,,6, (V) Hex.7, 7/ - UNFA 6 6 7 9 Ø, 6 SETTING RANGE 7 Min - Max [bar] No emergency Push pin Handknob 7 6.

7. Cartridge SAE ELECTRO-proportional pressure reducing valve Flow................................. l/min Max working pressure in................. bar Max working pressure in.................. bar Max working pressure in................... bar Leakage.......................... cc/min Max current at Vcc...................mA Max current at Vcc....................6mA PWM................................. Hz Hysteresis.................................% Cartridge tightening torque................. Nm Ring nut tightening torque................... Nm Weight (with coil)........................., Kg Cavity...................... C page Body......................... 7 page 7 Coil (to be ordered separately)...... 9 page 79 Regulated pressure [bar] 6,...6.. Vdc......6 Vdc Current [A], CH Hex. Ø6, / -6 UNF-A 9, Ø, Ø, 7 SETTING RANGE Min - Max [bar] Without filter With filter No emergency Push button 6. 7

6. Cartridge SAE way flow regulator valve Max working flow in.................... l/min Max working pressure in ::............. bar Leakage.......................... cc/min Seals...........................NBR and PTFE Cartridge tightening torque.................. Nm Ring nut tightening torque................... Nm Weight (with coil)........................,6 Kg PWM.................................. Hz Hysteresis................................ % Max current at Vcc.................... 9mA Max current at Vcc................... ma Cavity...................... C page Body......................... 7 page 9 Coil (to be ordered separately)...... 9 page Ø 6, Hex.7 7/ - UNFA Ø 7, Port under pressure Port under pressure - - - - - - - P-P [bar] Ø, 6,,,,,,6,7,,9 (V),,,6,,,,,6, (V) FLOW RANGE 6 Min - Max [l/min] No emergency Unscrew type 7 6.

6. Cartridge SAE way flow regulator valve Max flow range in..................... l/min Max working pressure in ::............. bar Leakage.......................... cc/min Seals...........................NBR and PTFE Cartridge tightening torque.................. Nm Ring nut tightening torque................... Nm Weight (with coil).........................,7 Kg PWM.................................. Hz Hysteresis................................ % Max current at Vcc.................... 9mA Max current at Vcc................... ma Cavity...................... C page Body......................... 7 page 97 Coil (to be ordered separately)...... 9 page 9 Ø Flow Range [l/min] 6 Port under pressure Port under pressure - - - - - - - P-P [bar] Hex. -/6 - UNF-A 7 6 69, Ø,,,,,,,6,7,,9 (V),,,6,,,,,6, (V) Ø, 6 FLOW RANGE 6 Min - Max [l/min] No emergency Unscrew type 6. 7