Basler DECS-250, Instruction Manual, Page: 53 / 352

9440300990 Rev J 37
DECS-250 Contact Inputs and Outputs
Contact Inputs and Outputs
Sixteen isolated, contact sensing inputs are available for initiating DECS-250 actions. Twelve sets of
output contacts provide annunciation and control.
Contact Inputs
BESTCOMSPlus Navigation Path: Settings Explorer, Programmable Inputs, Contact Inputs
HMI Navigation Path: Not available through HMI.
Sixteen contact inputs are provided for initiating DECS-250 actions. Two of the contact inputs are fixed-
function inputs: Start and Stop. The remaining 14 contact inputs are programmable. An additional 10
contact inputs are available with the optional Contact Expansion Module (CEM-2020). Contact Basler
Electric for ordering information.
All contact inputs are compatible with dry relay/switch contacts or open-collector outputs from a PLC.
Each contact input has an isolated interrogation voltage and current of 12 Vdc at 4 mAdc. Appropriate
switches/contacts should be selected for operation with this signal level.
Note
The length of wiring connected to each contact input terminal must not
exceed 150 feet (45.7 meters). Longer wiring lengths may allow
induced electrical noise to interfere with the recognition of contact
inputs.
Start and Stop Inputs
The Start and Stop inputs accept a momentary contact closure that enables (Start) and disables (Stop)
the DECS-250. If the DECS-250 receives Start and Stop contact inputs simultaneously, the Stop input
takes priority. Start contact input connections are made at terminals START and COM A. Stop contact
input connections are made at terminals STOP and COM A.
Programmable Inputs
The 14 programmable inputs can be connected to monitor the status of excitation system contacts and
switches. Then, using BESTlogic™
Plus programmable logic, these inputs can be used as part of a user-
configured logic scheme to control and annunciate a variety of system conditions and contingencies.
Information about using the programmable inputs in a logic scheme is provided in the
BESTlogicPlus
chapter.
To make the programmable contact inputs easier to identify, you can assign a custom name
A
that relates
to the inputs/functions of your system. Figure 23 shows a portion of the BESTCOMS Plus
®
Contact Inputs
screen where each of the 14 inputs can be assigned a custom name.