The innings sparked into life when skipper Daniel Flynn joined Dean Brownlie at the loss of the first wicket, triggering a rapid partnership that set the Knights on their way.
Flynn was run out but Brownlie continued on, notching 61 before handing duties over to Mitchell Santner and Daryl Mitchell.
Santner took up much of the slack with a run-a-ball 45 before Mitchell, who finished not out on 100 even, took up the attack.
His century came off 98 balls and looked likely to be enough with the Volts still requiring more than 10 runs per over with five remaining, but the Volts began their run at just the right time.
More than 600 runs were scored in 100 overs of play - proof the Bay Oval surface continues to produce fine games of cricket.
Scorecard:
Northern Knights
AP Devcich lbw b JA Duffy 2
DG Brownlie b JA Duffy 66
DR Flynn run out (SR Wells) 24
DJ Mitchell not out 100
CJ Anderson c DC de Boorder b JA Duffy 6
MJ Santner c IA Robertson b NL McCullum 45
TL Seifert run out (JL Finnie/DC de Boorder) 25
SC Kuggeleijn c AJ Redmond b JA Duffy 0
IS Sodhi c DC de Boorder b SR Wells 8
JJ Boult not out 12
Extras (b 4, lb 9, wd 7, nb 0) 20
Total (for 8 wickets, 50.0 overs) 308
Fall: 1-9 (AP Devcich, 3.3), 2-70 (DR Flynn, 11.3), 3-131 (DG Brownlie, 23.4), 4-139 (CJ Anderson, 25.1), 5-217 (MJ Santner, 38.6), 6-267 (TL Seifert, 44.6), 7-272 (SC Kuggeleijn, 45.4), 8-281 (IS Sodhi, 46.5)
Bowling: N Wagner 10-0-72-0, JA Duffy 10-0-64-4, SR Wells 10-1-37-1, JM McMillan 7-0-43-0, NL McCullum 10-0-50-1, JL Finnie 3-0-29-0.
Otago Volts
AJ Redmond c DG Brownlie b IS Sodhi 64
SR Wells c A Verma b IS Sodhi 93
MG Bracewell c DJ Mitchell b SC Kuggeleijn 83
NL McCullum c DJ Mitchell b IS Sodhi 5
DC de Boorder not out 25
IA Robertson c DJ Mitchell b MJ Santner 7
JL Finnie not out 18
Extras (b 4, lb 3, wd 6, nb 1) 14
Total (for 5 wickets, 49.3 overs) 309
Fall: 1-134 (AJ Redmond, 27.5), 2-245 (MG Bracewell, 40.6), 3-247 (SR Wells, 41.5), 4-267 (NL McCullum, 45.3), 5-282 (IA Robertson, 47.2)
Bowling: SC Kuggeleijn 7.3-0-51-1 (2w, 1nb), A Verma 7-0-37-0, MJ Santner 10-0-60-1, IS Sodhi 10-0-48-3, CJ Anderson 5-0-35-0, JJ Boult 10-0-71-0.