Antunes, AJ VS-350 owner manual Technical Theory of Operation

Variety STeamer

Maintenance (continued)

Technical Theory of Operation

When the Rocker Switch (power On/Off) is ON, line voltage flows to the primary side of the step down transformer. The transformer’s secondary side supplies 12 and 24 VAC to the Control Board.

Once powered, and provided that the generator’s tem- perature is below the setpoint temperature, the Control Board calls for heat by supplying 3 to 5 VDC to the Solid State Relay terminals 3 (+) 4 (-). Once powered, the Solid State Relay then closes terminals 1 and 2, which allows line voltage to flow to the generator.

As the generator begins to heat up, a type “K” thermo- couple monitors the internal generator temperature. As the heat continues to increase, so does the thermocou- ple’s DC millivolts.

Once the generator’s temperature approaches the set- point temperature, the Control Board begins to pulse the VDC to the Solid State Relay. The generator’s VAC and AMPS will also pulse during this point. When the generator’s temperature is between the recommended setpoints of 375 - 400° F (190 - 204° C), the thermo- couple generates approximately 7.5 - 8.5 DC millivolts. The Control Board receives these millivolts and pro- ceeds to remove the 3-5 VDC to the Solid State Relay since the heating circuit has now become satisfied.

Then, the Solid State Relay terminals 1 and 2 open up, and the generator stops heating. The heating circuit cycles on and off as needed, even at idle.

When the Single Shot button is pushed, it signals the Control Board to initiate a single shot of steam. The Control Board then supplies 24 VAC to the Solenoid Valve for a split second. The Solenoid Valve opens and allows approximately 3/4 - 1 ounce (4 to 5 tablespoons) of water to be disbursed onto the generator surface for steaming. The water is immediately converted into steam, which is forced up through the black Manifold Orifices to steam the product within the baskets.

Each of the four channel buttons can be custom pro- grammed for cycle time, time between when each steam shot occurs, and water volume used per each shot (See the Programming section of this manual). An audio signal will sound for three seconds at the end of the cycle.

Two safety devices are incorporated into the VS-350:

•Hi-Limit Thermostat

•Pressure Relief Plunger

If the heating circuit continues to call for heat and the generator overheats, a manual resettable Hi-Limit Thermostat will trip and open the generator circuit.

If water and or steam pressure builds up beneath the black Manifold Plate (due to restricted Manifold Plate orifices), a Pressure Relief Plunger will elevate and vent the steam pressure above the manifold plate.

NOTE: If any of these conditions should arise, the root cause must be determined and corrected. See the Maintenance section of this manual for further details.

NOTE: All direct water fed units require a Water Pressure Regulator. It should be set to 20-25 psi (1.4-1.7 kg/cm2 or 138-172 kPa). Failure to install a Water Pressure Regulator will result in poor steam- ing and flooding of the steam generator.

18 P/N 1010745 Rev. G 03/06