AP21EX4 is a piston drive pilot operated poppet 2-port solenoid valve with pressure and explosion proof construction (Ex d IIB T4), an NC type that opens when energized. It is used for air, water, kerosene and oil, with ports from Rc1 1/4 to Rc2 and 32 to 50 flange.


| Working Fluid | Air / water / kerosene / oil (50 mm²/s or less) |
| Valve Structure | Pilot operated poppet, piston drive, NC (open when energized) |
| Explosion Protection | Pressure and explosion proof construction Ex d IIB T4 (group IIB / temperature class T4) |
| Explosion-Proof Certification Bodies | Japan certification (TIIS) or Korea certification (KOSHA), selected by order code (blank = TIIS, KR = KOSHA) |
| Certification Numbers | AC coil (class 180 (H)): Japan No. TC20594 / Korea 16-AV4BO-0150X; DC coil and diode integrated AC coil (class 130 (B)): Japan No. TC20618 / Korea 16-AV4BO-0147X |
| Atmosphere | Outdoors / explosive gas (group IIB / temperature class T4) |
| Working Pressure Differential | 0.05 to 1.2 MPa (refer to max. working pressure differential by model) |
| Max. Working Pressure | 1.6 MPa |
| Proof Pressure | 3.2 MPa (water pressure) |
| Fluid Temperature | -10 to 60 °C (no freezing) |
| Ambient Temperature | -10 to 50 °C |
| Coil Thermal Class | AC coil class 180 (H), DC coil class 130 (B), AC diode integrated coil class 130 (B) |
| Valve Seat Leakage | 1 cm³/min (ANR) or less (air, measured at 0.05 to 1.2 MPa) (400 or less for PTFE seal) |
| Degree of Protection | IP65 or equivalent |
| Mounting Orientation | Free (within working pressure differential range) |
| Port Size | 32A: Rc1 1/4, 32F: 32 flange, 40A: Rc1 1/2, 40F: 40 flange, 50A: Rc2, 50F: 50 flange (JIS B2210 10K flange; the companion flange is not enclosed with the product and must be purchased separately) |
| Min. Working Pressure Differential | 0.05 MPa |
| Max. Working Pressure Differential (MPa) | Air AC 1.2 / DC 0.6, water and kerosene AC 1.0 / DC 0.6, oil AC 0.6 / DC 0.6 (all models; the DC column also applies to the diode integrated coil on AC power) |
| Flow Characteristics | -32A and -32F: orifice ø35 mm, Cv 25, effective cross-sectional area 460 mm²; -40A and -40F: ø43 mm, Cv 34, 625 mm²; -50A and -50F: ø53 mm, Cv 53, 975 mm² |
| Body / Valve Seal / O-Ring Material | Body: bronze (standard) or stainless steel; combinations: 0 (standard) bronze, NBR seal and NBR O-ring / B bronze, FKM seal and FKM O-ring / C bronze, PTFE seal and FKM O-ring / D stainless steel, NBR / E stainless steel, FKM / F stainless steel, PTFE seal and PTFE O-ring; H to N are the oil-prohibited treatment options of the same combinations |
| Coil | Code 3: thermal class 130 (B) explosion-proof coil (for DC); code 4: thermal class 180 (H) explosion-proof coil (for AC); code 5: thermal class 130 (B) diode integrated explosion-proof coil (for AC) |
| Applicable Cable O.D. | ø7.5 to ø9.5 / ø9.5 to ø10.5 / ø10.5 to ø11.5 / ø11.5 to ø13.5 (order codes 9 / 10 / 11 / 13) |
| Options | Manual override (locking) |
| Rated Voltage | 100 VAC 50/60 Hz, 200 VAC 50/60 Hz (options: 12 VDC, 24 VDC, 48 VDC, 100 VDC) |
| Apparent Power / Power Consumption | Apparent power: holding 18 VA (50 Hz) / 15 VA (60 Hz), starting 29 VA (50 Hz) / 24 VA (60 Hz); power consumption: AC 50/60 Hz 8/7 W, DC 11.6 W |
| Weight | 32A: 4.2 kg, 32F: 7.7 kg, 40A: 5.2 kg, 40F: 8.7 kg, 50A: 6.7 kg, 50F: 10.7 kg |