Emerson Fluid Chiller Guía para resolver problemas descargar pdf (Pagina 41)

Regulators

Emerson Climate Technologies

Upstream Regulators

The sole function of the Evaporator Pressure Regu-

lator is to prevent the evaporator pressure from falling

below a predetermined pressure setting. This enables

the system to meet certain load requirements over a

wide range of conditions and offers improvement over

the simple “on-off” compressor control usually provided

by thermostats or pressure switches.

Downstream Pressure Regulators

Suction pressure regulators are used to prevent

compressor motor overload. By throttling the suction gas

ow during high load conditions, the compressor motor

is permitted to remain within current draw limitations.

Often referred to as holdback valves, crankcase pres-

sure regulators or suction pressure regulators, they also

serve many other useful applications.

A downstream pressure regulator can be direct acting

such as an OPR valve. These are hermetically sealed,

non-repairable outlet pressure regulators for use on low

capacity systems.

Figure 3: EPRB(S) Brass Body

Upstream Pressure Regulator with Suction Stop Option

Valve Adjustable Range

EPRB(S)-12 thru -20 0 to 110 psig

0 to 50 psig

IPR-6, -10 30 to 100 psig

65 to 225 psig

0 to 60 psig

OPR-6, -10 50 to 130 psig

100 to 225 psig

Adjustable Range Table

Voltage Cycles

120 50-60 Hz, AC

208-240

Standard Voltage & Frequencies Table

Series EPRB & IPR

These are all upstream regulators which can be

selected from the capacity charts available. Combin-

ing the regulator with a suction stop or shutoff solenoid

will cause the regulator to act as a suction stop valve.

Certain basic design operating condition data must be

determined to properly apply the regulator. For best

results, follow the simple procedure outlined below.

To select the proper regulator port size, the following

information is required:

1. System refrigerant (R134a, R22, R404A/R507A).

2. The required pressure setting (lowest allowable

evaporator pressure and corresponding refrigerant

saturation temperature).

3. The system suction pressure at the regulator outlet

(suction pressure where compressor capacity bal-

ances with system load) making allowance for any

common suction line pressure drop.

4. Pressure drop across regulator port. Subtract suction

pressure (3) from regulator set point (2).

5. Evaporator load in tons at regulator setting (required

minimum evaporator saturation temperature).

With the above information, select the proper regula-

tor as follows:

1. Select the valve extended capacity table from that

page which covers the system refrigerant.

2. Find the required evaporator saturation temperature

column.

3. For the available regulator pressure drop, nd the

rated capacity for each regulator port size.

4. Select the proper port size from the capacity which

matches the evaporator load.

1 2 ... 36 37 38 39 40 41 42 43 44 45 46 ... 71 72

Comentarios a estos manuales

Sin comentarios

Emerson Fluid Chiller Guía para resolver problemas Pagina 41

Comentarios a estos manuales

Relacionado con productos y manuales para No Emerson Fluid Chiller