Watlow MLS-PM, Руководство пользователя

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Introduction
MLS User’s Guide 11
Expanded Parts List
The Expanded Parts List contains a technical description of each
component of your MLS Controller.
MLS Processor Module Technical Description
The MLS Processor Module (MLS-PM) is housed in an eighth-DIN
panel mount package. It contains the power supply circuits, the CPU,
RAM with a built-in lithium battery socket, EPROM, serial
communications, digital I/O, and the LCD screen and touch keypad.
Here's a side view of the MLS-PM:
• Screw terminals connect the power inputs and outputs.
• Input power is 10-28 Vdc at 1 amp.
• The +5 Vdc, 750 mAdc output power supply powers the MLS-AIM.
• A 50-pin flat ribbon cable connects the digital inputs and outputs to
the 50-pin terminal block (TB-50).
• The MLS uses 6-pin telephone-style connectors for internal and
external communications.
The firmware's operating intelligence resides in the plug-in EPROM, so
it's easy to update or change the MLS' firmware. The MLS stores its
operating parameters in battery-backed RAM, so if there's a power loss
the operating parameters are unchanged. The battery has a ten year shelf
life, and it is not used when the unit is on.
The CPU microprocessor performs all calculations for input signal
linearization, PID control, alarms, and communications.
The telephone connectors on the rear of the MLS-PM are used for:
• Communications to the MLS-AIM.
• RS-232 or RS-485 communications to an optional computer.
• For OEM customers, communications to the optional MLS Smart I/
O Module (MLS-SIOM).
The System safe output is Low (On) when the CPU is running; it keeps
a solid state relay closed. If the CPU stops working, the output goes
High (Off) and the SSR opens.