In September 2014, I noticed that street lights were coming on during the day – a fault known as ‘day burn”.
In response to my questions, Devon County Council said this was because the computer-based Central Management System lost communication with the area nodes on the top of some street lights that control the rest of the lights in the area. For obvious safety reasons, the default setting when this happens is that all street lights are switched ON.
Thinking that DCC hadn’t installed enough area nodes to cover Cowick adequately, I put in a Freedom of Information request. Here is the response:
Environmental Information Regulations 2004 Information Request: IR2396596
Date of Request: 15 January 2015
Date of Disclosure: 02 February 2015
Devon County Council’s response is provided below in green text:
Q1 Can you tell me how many area nodes were initially installed to control the street lights in Cowick?
Four area (Branch) nodes control the street lights in Cowick Ward.
Q2 Have any additional area nodes been installed to rectify the system failure in the summer?
No additional area nodes were installed.
Q3 Can you identify each and every area node (street and lamp-post number) being used to control street lights in Cowick?
The area nodes are located at: Street light number 9 Dunsford Road, Street light number 37 Dunsford Road, Street light number 1 Charnley Avenue, and Street light number 12 Little Johns Cross Hill.
Q4 If no additional area nodes have been installed since the summer, what actions have been taken by both DCC and the system manufacture/designer/installer to prevent a re- occurance of ‘day-burn”?
The four area nodes control nearly 500 individual lights in Cowick Ward and each can control up to 250 lights, so the existing nodes are sufficient for the existing ward and any future additions that might arise from new residential developments. Among the lights controlled by an area node, up to three lights can be designated as booster units to assist combinations.
Day burning faults can arise from a fluctuation in the power supply, loss of communications or component failure, so any future occurrence would need to be investigated and appropriate action taken. When day-burning persists and radio communication appears to be the problem, then the County Council will work with the manufacturer to resolve this as quickly as possible. This could be a re-configuration of the communication network in the area by re-assigning booster nodes, or even relocation of the area node to a better position.
“Day burn’ also happens for a few days when DCC are placing new street lights under control of the Central Management System. No, I can’t explain why, but I’ve asked DCC!