Middleby Marshall PS540 Door Safety Switch, Blower Switch, Heat Switch, Temperature Controller

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SECTION 3

OPERATION

II.COMPONENT INFORMATION AND LOCATION (Figures 3-1 and 3-2)

A. Door Safety Switch

The Door Safety Switch is located at the lower left side of control panel opening. Opening the control panel door permits this switch to open, disconnecting power to all electrical controls.

CAUTION

Do NOT touch the wires going to this safety switch. Current is always present.

B. Blower Switch

The blower switch has two positions. The switch must be “ON” or “I” for the burner to come on and permit the oven to warm up. The fan circulates the air throughout the oven and must stay on during baking and during the cool down cycle above 200°F (93°C) to prevent blower bearing damage. To protect the blower motor and bearings a thermostatic override is built into the oven. If the tempera- ture inside the oven is over 180°F (82°C) the main blower will continue to run after the blower switch is turned to the “OFF” or “O” position.

An air pressure switch monitors the air flow from the blower, acting as a safety interlock for the burner. The

burner cannot light, if the air switch does not sense air flow off the main blower fan.

C. Heat Switch

Turning the HEAT switch to “ON” or“I” will initially set up the oven purge circuit. After approximately 30 seconds, the burner lights. After the burner is lit, a flame sensor sends a signal to the ignition module to stop the spark. The burner will run unless the flame sensor does not detect a flame or the heat switch is turned to the “OFF” or “O” position.

The HEAT switch is in series with the burner blower motor centrifugal switch, the high-temperature safety switch, and the blower fan air pressure switch. All three safety switches must be closed for gas to flow and the burner to light.

D. Temperature Controller

The temperature controller is a solid-state, on/off type to maintain the operator-set temperature. The temperature controller continuously monitors the oven temperature and turns on the modulating solenoid valve in a gas-heated oven. The heat is on for the time required to maintain a constant oven temperature.

The temperature controller contains a low-limit switch which allows the oven to cool down to 200°F (93°C) before shutting off the blower. A high-limit indication (ALM 1) will appear on the display if the oven reaches 650°F (343°C).

Figure 3-2. Interior View of Machinery Compartment and Control Console

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Contents Owners operating Page Middleby Marshall IiiTable of Contents Section Description Model IdentificationPS540 Series Oven Specifications II. Principle of AIR Flow Heat Transfer and How It WorksII. Principle of AIR Flow Air FingersPS540-Series Oven Components Locations III. Component Function FigureIII. Component Function Conveyor Motor and Conveyor BeltBlower Fan Gas BurnerCooling Fan Cooling Fan See FigureAir Fingers and Blank Plates See Figure F1. Air Fingers F2. Blank PlatesSection Installation UnloadingPS540 Oven Installation Required Kits and Equipment Parts List for Series PS540 GAS Oven Installation KITModel PS540 Single Oven Option Base with Legs and Top Model PS540 Double Oven Option Base with Legs and Top Model PS540 Triple Oven Option Base with Outriggers and Top Model PS540 Single Oven Dimensions Model PS540 Double Oven Dimensions Restraint Cable Installation Model Triple Oven DimensionsSection Installation II. Ventilation Guidelines Ventilation Hood 10. Vent HoodIV. Electric Supply for GAS- Heated Ovens 11. Typical Gas Oven Data PlateGAS Supply for GAS Heated Ovens 12. Junction Connection BoxVI. Conveyor Rear Stop and END Stop Installation Section Installation Section Operation Control FunctionsDoor Safety Switch Blower SwitchHeat Switch Temperature ControllerConveyor Measuring Conveyor SpeedSee Figures 3-4 III. STEP-BY-STEP Operation Control Panel Daily Startup Procedure II. Normal Operation STEP-BY-STEPSP Lock IV. Quick Reference Troubleshooting SymptomSection Maintenance Maintenance Daily ExteriorCooling Fan Crumb Pans FigureII. Maintenance Monthly Removing Conveyor From Oven For CleaningSection Maintenance Air Fingers Disassembly For Cleaning Standard FingersCleaning the Window Reassembly of Air FingersExtended Lip Tab on Outer Plate Flange Finger Manifold Section Maintenance Reinstall End Plugs Conveyor Reassembly Into Oven Checking Conveyor Belt TensionConveyor Belt Link Removal Attaching Drive Chain Replacing Conveyor BeltLower End Plug III. Maintenance Every 3 Months Cleaning the Blower/Fan MotorVentilation Electrical TerminalsChecking the Blower/Fan Belt Split-belt Conveyor Shaft Cleaning Blower Fan Shaft Bearing LubricationSection Maintenance IV. Maintenance Every 6 Months Important NoticesKEY Spare Parts KIT PS540-SERIES GAS Oven KEY Spare Parts KIT, p/n 36805 FigureSection Troubleshooting Section Troubleshooting Parts List English Oven PANELS, Window and Legs NUT, 3/8″-16 Nylon Insulated L/N ZCSection Parts List Control Panel English Blower and Shroud English Conveyor English Split Belt Conveyor English GAS Burner and Piping Assembly English Machinery Compartment Section Parts List Section Electrical Schematics Section Electrical Schematics Section Electrical Schematics Section Electrical Schematics Page Hour Service Hotline

PS540 specifications

The Middleby Marshall PS540 is a state-of-the-art conveyor pizza oven that has garnered significant attention in the commercial kitchen world due to its advanced features and capabilities. This oven is designed to meet the high-volume demands of pizzerias, restaurants, and food service establishments, offering efficiency without sacrificing quality.

One of the standout features of the PS540 is its innovative air impingement technology. This system utilizes powerful jets of hot air that circulate around the pizza, ensuring even cooking and browning. The result is a perfectly cooked pizza with a crispy crust and melting cheese, all while reducing cooking times significantly compared to traditional ovens. The efficiency of the PS540 allows operators to increase output, making it a valuable asset during peak hours.

Another key characteristic of the PS540 is its adjustable conveyor speed, which enables operators to customize cooking times based on the specific menu items being prepared. This flexibility ensures that various pizzas, from thick crust to thin crust, can be cooked to perfection. The conveyor design also facilitates a seamless workflow in busy kitchens, allowing for easy loading and unloading of pizzas.

In addition to its cooking capabilities, the PS540 boasts a user-friendly control panel, featuring intuitive digital controls for temperature and cooking times. This user-focused design simplifies operation, allowing staff members to easily program the oven for consistent results. Furthermore, the oven's durable construction and high-quality materials ensure reliability and longevity, minimizing maintenance needs and downtime.

Energy efficiency is a critical consideration in commercial kitchens, and the Middleby Marshall PS540 stands out in this area as well. By optimizing airflow and heat transfer, the oven reduces energy consumption while maintaining exceptional performance. This not only contributes to lowering operational costs but also aligns with sustainability efforts in food service.

Safety features, such as cool-touch exteriors and integrated ventilation systems, further enhance the PS540's appeal, ensuring that it meets the rigorous standards required in commercial kitchens. Overall, the Middleby Marshall PS540 not only elevates pizza quality but also enhances operational efficiency, making it an indispensable tool for any high-volume restaurant or pizza establishment. With its blend of technology, performance, and ease of use, the PS540 sets a new standard for conveyor pizza ovens in the culinary landscape.