Series 4 PLUS Cartridges Offer Higher Flows with Lower Pressure Losses

Logic Element and Check ValveSeries 4 PLUS cartridge valves with optimized cavities offer high flow performance - less than 100 psi (7 bar) pressure loss at 200 gpm (760 l/min) flow. This performance is comparable to DIN 25 and DIN 32 valves and is 50% to 80% more efficient than a standard Sun Series 4 equivalent functional cartridge and cavity.

Sun's Series 4 PLUS cartridge valves feature the same high pressure performance as Sun's standard valves, 5000 psi (350 bar) on all ports. Check valves and logic elements are both currently available in PLUS performance with more functions to come.

For optimized efficiency and performance, Series 4 PLUS should be paired with the new, optimized T-18AU and T-19AU cavities. The new Series 4 Plus Cavitycavities include an undercut in the port two area. Since Series 4 PLUS valves are the same size as standard Series 4 valves, both Series 4 and 4 PLUS cartridges are physically interchangeable in both standard and optimized cavities. To obtain full benefits of Series 4 PLUS products, the cartridge and cavity must both be of Series 4 PLUS configuration. To improve existing Series 4 flow performance, standard valves can be installed in optimized cavities. PLUS valves in optimized cavities will deliver maximum flow performance.

Benefits of PLUS performance include:

  • Better availability than comparable DIN valves,
  • Lower cost and smaller assemblies,
  • Reduced size compared to slip-in and competitive cartridge valves,
  • In some applications, one Series 4 PLUS valve in an optimized cavity may replace two standard valves in standard cavities.

Series 4 PLUS valves come with all of Sun's hallmark attributes - availability, reliability and superior performance. Local customer service, technical support, and inventory are available from Sun worldwide authorized distributors. When not in local inventory, Sun manufactures to our customer's request date.

The following table provides an overview of the introductory offering of Series 4 PLUS products with links to the individual product pages. Contact your distributor for more information.

FunctionSymbolNominal CapacityCartridge ModelCavity
Free Flow Nose to Side Check Valve  CXKA Function Symbol 240 gpm
(900 L/min.)
CXKA T-18AU
Free Flow Nose to Side Check Valve with Bypass Orifice  CNKC Function Symbol 180 gpm
(680 L/min.)
CNKC T-18AU
Pilot-to-Close Check Valve  COKA Function Symbol 240 gpm
(900 L/min.)
COKA T-19AU
Vent-to-Open, Spring Biased Closed, Unbalanced Poppet Logic Element, Pilot from Source 1  LOKA Function Symbol 300 gpm
(1100 L/min.)
LOKA T-19AU
Vent-to-Open, Spring Biased Closed, Unbalanced Poppet Logic Element, Pilot from Source 2  LOKB Function Symbol 300 gpm
(1100 L/min.)
LOKB T-19AU
Vent-to-Open, Spring Biased Closed, Unbalanced Poppet Logic Element, Pilot from Source 1 or 2  LOKD Function Symbol 300 gpm
(1100 L/min.)
LOKD T-19AU
Pilot-to-Close, Spring Biased Closed, Unbalanced Poppet Logic Element  LOKC Function Symbol 300 gpm
(1100 L/min.)
LOKC T-19AU
Pilot-to-Close, Spring Biased Open, Unbalanced Poppet Logic Element  LOKO Function Symbol 300 gpm
(1100 L/min.)
LOKO T-19AU

Click here for Sun's Series 4 PLUS printable brochures.