ZKC center controller reported issuing a traffic advisory too late due to an excessive work load.

Attributes
ACN	1505963
Time
Date	201712
Local Time Of Day	1201-1800
Place
Locale Reference	ZKC.ARTCC
State Reference	KS
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Route In Use	VFR Route
Flight Plan	VFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	Cruise
Route In Use	None
Person 1
Function	Enroute Instructor
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 4
Events
Anomaly	ATC Issue All Types Conflict Airborne Conflict Deviation - Procedural Published Material / Policy

Narrative:

I was the OJT instructor for the combined sectors radar assist position (d-side). We were very busy; this is nothing new for the sectors. Our facility was cited as failing to split sectors and failure to effectively assign d-sides to sectors and was often unnecessarily overloaded. Our staffing is far below a safe number as was noted by the erc (employee review committee) and as negligently staffed. All these factors play into this situation. While we were overly busy; trying our best to keep up with the traffic demand we as a sector failed to issue traffic merging procedures early enough to a VFR aircraft receiving radar traffic advisories. This VFR was at 5500 ft and was definitely within 100 ft and 0.5 miles of another non radar identified VFR aircraft at 5400 ft. A traffic call was not made until the aircraft was within 1-2 miles. This is a devastating situation; but it's due to the lack of safety culture from our upper facility management.do what's right. We should split sectors and always have the staffing to do so; without question; no matter what the day or the forecast number of flights.

Original NASA ASRS Text

Title: ZKC Center Controller reported issuing a traffic advisory too late due to an excessive work load.

Narrative: I was the OJT Instructor for the combined sectors Radar Assist position (D-side). We were very busy; this is nothing new for the sectors. Our facility was cited as failing to split sectors and failure to effectively assign D-sides to sectors and was often unnecessarily overloaded. Our staffing is far below a safe number as was noted by the ERC (Employee Review Committee) and as negligently staffed. All these factors play into this situation. While we were overly busy; trying our best to keep up with the traffic demand we as a sector failed to issue traffic merging procedures early enough to a VFR aircraft receiving radar traffic advisories. This VFR was at 5500 ft and was definitely within 100 ft and 0.5 miles of another non radar identified VFR aircraft at 5400 ft. A traffic call was not made until the aircraft was within 1-2 miles. This is a devastating situation; but it's due to the lack of safety culture from our upper facility management.Do what's right. We should split sectors and always have the staffing to do so; without question; no matter what the day or the forecast number of flights.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.