ADC AD-464 service manual Sprinkler System Description

SECTION VIII

SPRINKLER SYSTEM

A. SPRINKLER SYSTEM DESCRIPTION

The sprinkler circuit on the dryer requires a dedicated single-phase (1ø) supply from the dryers' voltage. The sprinkler hi-limit temperature is 700º F (371.11º C). In the event of a hi-limit condition, contact #7 and contact #8 on the sprinkler controller will open, disabling the 120 volt supply to the under voltage disconnect. The disconnect will open thereby disabling the power (electrical supply) to the dryer. Another set of contacts will close, sounding the alarm horn and energize the sprinkler pneumatics. This will allow air into the sprinkler valve causing it to open which will allow water to flow.

NOTE: The sprinkler as well as the alarm will remain on until the "amber" colored sprinkler reset button

is pressed and the temperature in the tumbler (basket) falls below 700º F (371.11º C).

1.Description Of Components

a.Resistive Temperature Device (RTD)

The RTD (Resistive Temperature Device) probe is located above the tumbler (basket). The probe is a 100 ohm (100 Ω ) platinum RTD. As

the drying temperature increases or decreases, the resistance value corresponds to the ambient temperature (i.e., 100 ohms [10 Ω ] will be equivalent to 32º F [0º C], 109 ohms [109 Ω ] will be equivalent to 37º F [24º C]).

b. Sprinkler Valve

The sprinkler valve is a 3-way, air piloted, normally closed (N.C.) solenoid valve.

With pilot air pressure applied, the valve opens allowing water to flow

c. Sprinkler Solenoid Valve

The sprinkler solenoid valve is a 3-port/2-posion solenoid valve that is used to supply pilot air to the sprinkler valve.

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