If you’re using debt collection you might want to add a new trap and apply this to the borrowers. Then select this borrower trap when you set up the debt collection parameters.
For example, you might specify "DCN" as the code for the charge, and "Debt collection notification" as the description.
You might want to set Trap on borrower validation to Yes, and leave all the other parameters as null or No. If you leave Alert for validation/activity trap set to null this means that the default alert BRWDLQGEN will be displayed for borrowers with this trap. If you wanted to, you could add your own alert and then select this as the Alert for validation/activity trap.
If a borrower has a debt collection record then you'll see the DCNWARN alert when you scan the borrower's barcode in Circulation.