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4.3 Commonly Asked Questions
Q. Can I have multiple MMI’s connected to one Controller?
A. The ability to connect more than one MMI to a PLC depends on the type of serial interface the PLC
has. PLCs with RS232 communications cannot be networked due to the nature of RS232 signal
requirements. PLCs with RS485 or RS422 can be networked, but, not all of these PLCs support
networking. The MMI supports networking on a limited number of PLCs.
Q. Can I down load a recipe?
A. Yes. To do this chain Special messages together with the recipe values as constants. Do not
assign any message text to these messages. The recipe download can then be activated by Function
key or MTR.
Q. Can I Have PC and MMI active at the same time?
A. Yes, the MMI PC port is always active for PC to MMI programming and MMI printout. The PC
port is NOT a pass through port to the PLC.
Q. Do I need to change any jumpers to go from one PLC type to another?
A. No. The PLC type is determined by the driver that is downloaded into the MMI at programming
time.
Q. Is there any way to completely erase the MMI memory?
A. Yes. The MMI memory can be initialized by the following procedure.
Caution!
All Message and Driver programming will be erased!
Make sure you want to do this!!!
1 Remove power from the MMI.
2 Hold the F5 and F8 Function keys for MMI-100 or Down Arrow and Enter keys for MMI-110 &
140 (the lower most right and left-hand key) down.
3 While holding the two keys down apply power to the MMI.
4 When the MMI displays “INITIALIZING ALL MEMORY” you can release the keys.
The MMI must be reprogrammed using the PC software.
Q. How Do I change the Battery?
A. There is none! The MMI requires no routine maintenance.
Summary of Contents for MMI-1 Series
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