Rockwell Automation Publication 1444-UM001D-EN-P - June 2018 73
Install the Dynamix 1444 Series Monitoring System Chapter 2
Tacho Signal from a Directly Connected Source
It is expected that a TSC Expansion module is the normal source of a tacho
signal for a system, however, each DYN module can accept up to two ‘local’ or
‘direct’ tacho inputs.
The local inputs are designed for situations where there is a TTL level tacho
signal available, a tacho sensor with an open collector output (such as NPN
type) or a connection to an opto output on another module. For any of the
three signal source types, connect the signal to terminal 17 and the common/
return connection to terminal 18.
Figure 30 - TTL Output* Transducer Connection
*Speed input signals must indicate “Low” by a voltage of 0V…2V and “High” by a voltage of 3V…5V.
IMPORTANT It is not recommended that multiple tacho inputs from across different 1444
Series DYN modules are connected to the same tacho source. The tacho
inputs are not isolated from other module circuitry.