Those are the conditions...but why...if I may ask? Does the VR cause issues? Thanks
VR works by utilizing moving components within the lens to stabilize the view. This is how VR claims to achieve additional exposure stops when hand holding ... it's working to negate your natural movement/shake.
The problem is ... when clamped down on a tripod, there is no movement to negate, yet the lens still engages these moving components. On a tripod, you don't need the lens to give you extra exposure stops ... the tripod does that for you. The tripod will let you make 30 second exposures if you want. When VR is engaged though, it's creating vibrations within the lens that now work against the tripod giving you the steady shot. Similar to using Mirror Up on a tripod to remove that shake, having the lens vibrate does not help at all, but actually can make things worse.