IDA4 Application. An example how one of our customers has used our IDA4 Alarm Controller
Application Note for the IDA4
A hand operated crane with electromagnet for moving scrap metal.
In this application, a hand operated crane at a steel plant, controlled by a Programmable Logic Control (PLC) is being used to move steel bars with a magnetic lifting system. The client needed to monitor the DC currents drawn by the electromagnet which are between 0.5 to 15 Amperes DC. They required:
- A low alarm to detect the magnet current dropping to less than 0.5 ampere
- A high alarm to detect the magnet current exceeding 15 Amperes
- A ‘window’ alarm that would be active between a minimum and maximum level.
We offered our IDA4 or our DIR4 set point controller for this application because:
- It has touch switch programming of the numbers on the 4.5 display
- Each output can be programmed as a high alarm, low alarm or window alarm.
- The alarm setting procedure is easy to understand and operate. To avoid relay chatter, you don’t have to understand dead band. For example, the instrument is scaled as 0-15.00 amperes, output one is set as a high alarm and is programmed to go into alarm condition at 14.9 amperes and come out of alarm condition at 14.3 amperes. You just need to program a turn on and turn off point.
- The control alarm or ‘window alarm’ uses a maximum and a minimum value. This function is useful if you want a monitor that a signal is between set levels. In this application because the crane was hand operated the client wanted to have visible indication. A red light if the current was above 14.9 amps, an orange light if the current was below 0.5 amps and a green light if the current was between 1.00 to 14.0 amperes.