Eemerson 2-Way Solenoid Valves types 200RB6T5T,240RA16T9T,240RA20T13M introduction

Directly actuated: The magnetic field of the

solenoid coil forces a movement of the plunger and

thus causes the opening of the valve seat.

Servo actuated: The magnetic field of the solenoid

coil is only utilized for the opening of the pilot valve

seat. The necessary energy to actuate the piston

or diaphragm of the main valve seat is provided by

the refrigerant flow and results in a certain pressure

drop.

Minimum pressure drop

Directly actuated solenoid valves do not require a

minimum pressure drop for proper operation.

Servo operated solenoid valves require a minimum

pressure drop of approximately 0.05 bar to remain

fully open. In case of insufficent refrigerant flow this

value will not be reached and the solenoid valve

may close unintentionally. These closures may lead

to malfunctions and oscillations in the refrigeration

circuit. Improper sizing of solenoid valves (i.e. use of

excessively large solenoid valves) is the main cause of

this effect. This is particularly important in capacity

controlled refrigeration circuits.

Therefore the decisive factor for proper solenoid

valve sizing is the respective capacity of the valve

and not its connection size.

Formula for calculating the actual pressure drop of

a solenoid valve:

∆ p1 = ∆ p2 x (Q n1 /Q n2 ) 2

∆ p1 :  Actual pressure drop

∆ p2 :  Nominal pressure drop at Q n1

Q n1 :  Calculated nominal capacity

Q n2 :  Nominal capacity of selected valve

Maximum Operating Pressure Differential

(MOPD)

MOPD is the maximum pressure differential between

inlet and outlet of the solenoid valve which permits

proper opening of the valve. When used with ALCO

AC solenoid coils all ALCO solenoid valves employ

25 bar MOPD.

Operation in conjunction with DC solenoid coils lead

to reduced MOPD values depending on valve type

and size.

The DS2 Chopper Plugs allow the use of

24VAC coils with 24VDC by converting the DC in

an AC voltage. Please contact ALCO application

engineering for additional details.

Eemerson 2-Way Solenoid Valves types 200RB6T5T,240RA16T9T,240RA20T13M Features

 Compact size

• Snap-on clip for attaching solenoid coils

• No disassembly necessary for soldering

Standards

• 240 RA 16T11 and 20 are CE marked per PED

Type  Nominal Capcity Q n (kW)

Liquid  Hot Gas  Suction Gas

R 404A  R 404A  kv-value ∆p min

R 134a  R 22  R 507 R 407C R 134a R 22  R 507 R 407C R 134a  R 22  R 507 R 407C  m 3 /h  bar

110 RB 2  3,5  3,8  2,5  3,6  1,6  2,0  1,7  2,1  0,2  0

200 RB 3  6,6  7,1  4,6  6,8  3,0  3,7  3,2  3,9  0,4  0,05

200 RB 4  15,5  16,8  10,9  16,1  7,1  8,8  7,5  9,2  0,9  0,05

200 RB 6  27,3  29,5  18,9  28,0  12,5  15,4  13,1  16,1  1,6  0,05

240 RA 8  36,3  39,3  25,2  37,3  16,7  20,5  17,4  21,4  4,2  5,6  4,6  5,2  2,3  0,05

240 RA 9  76,2  82,5  52,9  78,4  35,1  43,1  36,5  44,9  8,8  11,7  9,7  10,9  4,8  0,05

240 RA 12  85,7  92,8  59,5  88,1  39,4  48,4  41,1  50,5  9,9  13,1  10,9  12,3  5,4  0,05

240 RA 16  139,1  150,5  96,5 142,9  64,0  78,5  66,6  81,9  16,0  21,3  17,7  19,9  8,8  0,05

240 RA 20  202,6  219,3  140,7 208,3  93,2 114,4  97,1 119,3  33,0  31,0  25,7  29,0  12,8  0,05