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General => Technical support => Topic started by: tkidder2 on August 03, 2004, 04:47:37 PM

Title: ttl input
Post by: tkidder2 on August 03, 2004, 04:47:37 PM

 Can the M series accept ttl level inputs?
What is max current required by input?

Title: Re:ttl input
Post by: support on August 09, 2004, 11:03:30 AM

The PLC's input cannot be connected directly to the M-series PLC inputs. You need to use a chip such as ULN2003A as an interface to convert TTL level inputs to NPN input that the PLC accepts.

However, on the expansion board EXP4040 there are 16 channel of HCMOS input but is reverse logic. i.e. 5V = OFF and 0V = ON. The specification of these inputs are the same as standard HCOMS ICs.