Malo Advisor No. 001.03

Malo is pleased to introduce a new microprocessor-based system for control of its crateless retorts. This proven retort control system accurately regulates the process sequencing, vent time, cook time, process temperatures, pressure cool time and pressure in a Malo Crateless Retort System.

System Description:

The heart of the system is a state of the art processor, with distributed 24 VDC, 4-20 mA analog inputs and outputs, and 24 VDC discrete inputs and outputs. The control program uses standard ladder logic sequencing for simplicity and ease of modification. Temperature and pressure are controlled using PID (Proportional, Integral, Derivative) control loops within the software, which interact with control valves to provide consistent, precise control.

Operator interface is provided by color CRT Plant Floor Graphic Terminals, which display the status of each individual retort. They also provide interface with the processor for the purpose of set-point modification and status update with menu driven software. This update can be developed either through the touch screen or through communication with a personal computer.

This system offers the latest technology in control, quality assurance, process flexibility, reliability, and security over conventional systems. The use of state of the art, off the shelf industrial components, coupled with more than 35 years crateless retort experience by Malo, provides the best possible value to the customer in the area of computer controlled crateless retort systems.

System Operation:

The system provides repeatable process control with little or no adjustment between batches. Pre-operational setup and adjustments are limited to inputting setpoints into the interface terminals. The set-points are cook temperature, blowdown pressure, cooling pressure, time of vent, time of cook, and time of pressure cool. The control system will retain and hold these values until the product changes or the recipe changes, requiring new values to be entered.

Safety Features:
The Malo Microprocessor based control system incorporates safety features designed to prevent unprocessed containers from passing through the retort due to operator error or misjudgment.

Once the top door has been closed and the START button depressed, the bottom door cannot be opened until a complete process cycle is accomplished. The top door can be opened again only after the system has been RESET.

The system also provides an interlock to prevent closing the top door with the can chute down. The system prevents the doors from opening while there is pressure in the retorts. The system also automatically controls the temperature and level in the reservoir tank and the level in the canals.

Hardware Provided:

A. These items are in NEMA 12 enclosures.


 1. Processor(s) - including appropriate discrete input and output modules, analog input and output modules, network communication modules and racks. The modules for each retort are located in the operator panels which are located at each pair of retorts. The processor is located in the first operator panel.

2. Touch Screen Color Terminal and Interface for each two retorts.

3. Solid state, programmable 2-pen recorder for each retort.

4. Power Supply and Power Distribution for instruments.

5. Can Counter(s)

6. Voltage Transformer for primary Operator Cabinet.

7. Operator Panel (A NEMA 12 enclosure) - Provides top and bottom door controls, can diverter and chute controls, power switch, start buttons, selector switches, indicator lights, solenoid valves and I-P valve positioners, and high and low level relays. (There is one panel for each two retorts.) IO modules for each pair of retorts are located in the operator panels.

B. Items provided for installation on retort.
  1. Pressure Transmitter.
2. Temperature Transmitter.

Software Provided:

A. Developed by and proprietary to Malo, Inc., and is provided for customer use on the quoted system.

B. Optional Software packages:
  1. Data Acquisition: This program records the data of each process, time stamps it and transmits it to a secure data base. The program inputs include the process number, the process recipe, and can count. The program prompts the operator to enter the FDA required temperature records and bleeder status, and the electronic signature required by the CFR21. We provide shift, daily, and monthly management reports with trending and alarms. The reports can be reviewed from any network PC.
2. Recipe Download: This program allows for the storage of all recipe set points and automatically enters the set points into the PLC. Recipes will be listed on a recipe download screen accessible from any touch screen panel.

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