Electronics Inc. • (574) 256-‐5001 • www.electronics-‐inc.com
7
Process Input Signal
The process input signal may come from either a current transformer or from a 0-‐10 Vdc signal source.
Motor Amperage with Current Transformer
A current transformer, typically rated 100:5, converts the wheel motor current of 100 amps down to five (5) amps.
The five (5) amp signal is then considered the “full-‐scale“ process input signal at the AC-‐24 Controller. The full-‐scale
range of the AC-‐24 Controller is set at 100.0.
Connect the leads of a 100:5 current transformer to Terminals #7 and # 5. A factory-‐installed current shunt at
those terminals converts the five (5) amp current transformer signal to a 0.05 Vac signal that is then scaled inside
the AC-‐24 Controller to the 0-‐10 Vdc range.
For smaller wheel motor applications, a smaller current transformer, such as 50:5, may be used. The Full Scale
Display Range must be reduced to 50.0 to match the current transformer rating. (See “Full Scale Display Range” in
Preliminary Settings in this manual.)
Motor Controller Signal 0-‐10 Vdc
Current transformers may not reflect actual motor current when a variable frequency motor speed controller is
used. The factory-‐supplied current shunt on Terminal #7 is ignored and a 0-‐10 Vdc signal is applied to terminal #6.
Verify that the 10 Vdc output from the motor speed control represents 100 amp full-‐load current. If the full-‐scale
range of the motor speed controller is set at a different value, the AC-‐24 Controller must be scaled to the same
value. (See “Full Scale Display Range” in Preliminary Settings in this manual.)
