CD were 367-7 at stumps with Cachopa stealing the limelight with a measured 123 off 210 deliveries.
The South African-born allrounder carved up 18 boundaries while occupying the crease for a shade more than five hours on a day that flirted with 30C temperatures in some areas of Hawke's Bay.
Former Black Caps leg spinner Tarun Nethula, at No 8, was the other major contributor for CD, racking 87 runs towards a possible maiden shield century.
He will resume with Black Caps fast bowler Adam Milne (38) when play resumes at 10.30am today.
Opener Jacob Duffy was the pick of the bowlers for Otago, taking 2-61 off 20 overs.
NZ Cricket convenor of selectors Kim Littlejohn yesterday said director of cricket John Buchanan had arrived early yesterday morning from Sri Lanka, where the Black Caps are playing their second test with aplomb, and was driving to Napier to watch the game between table toppers CD and second-placed Otago.
Littlejohn said it was pleasing to see Cachopa finding traction in back-to-back matches.
"He's doing everything you could ask for and it's great to see he's backing up with hundreds consistently," Littlejohn said, adding quite often players at domestic level posted a ton but failed to reload and fire.
While it was a fantastic start to the 2012-13 summer for Cachopa, who also shone in CD's losing HRV Cup match in Hamilton last Friday night, Littlejohn emphasised it was vital not to rush players of his calibre into the international arena too early.
"We're often guilty in New Zealand of elevating players to the international level as soon as they make a big score or two.
"It's a fantastic start for Carl in scoring runs and we hope he keeps doing that because we need some new guys to do that," Littlejohn said, adding Crowe was scouting for NZ Cricket in Auckland while ex-international player and coach Glenn Turner was fulfilling that role in the south.
Cachopa said: "I'm just happy to be doing well and contributing to the team with the bat and, when I get the opportunity, with the ball. I'll try to do my best there as well."
He was comfortable coming at No 3 to find the top order had had the wobbles, knowing the Stags could bat deep.
"It showed today with Tarun who is on 80 odd not out and Milney on 30-odd not out so these guys have consistently been able to put runs together down the order so they are very useful in the scheme of things."
Cachopa felt with the first day and a fresh wicket CD expected a few wickets to tumble but they were happy the boys were able to stay in to post 367-7 at stumps.
He hadn't dwelled on what Littlejohn or other selectors were thinking about his bumper knocks that started late last summer.
"To be honest I haven't thought of that at all. My goal is to do the job for CD so I haven't thought or spoken about that to anyone.
"Every cricketer likes to represent their country so I'm not saying I don't want to play for the Black Caps but at this stage I'm trying to do my best for CD."
With captain Kieran Noema-Barnett losing the toss, Cachopa said the pitch was good and challenging as wickets tumbled throughout the day.
"When you can put a few partnerships together then you're able to guts it out to post a good team total so I'm really stoked for Milney and Tarun who are doing a great job."
Nethula returned the compliment: "Chops, the fine batsman that he is, again set us up so Milney and I want to see how far we can go."
He said the coaching stable had impressed on all players the need to take pride in their batting and it was working.
"We've all been putting partnerships together from top to bottom so it's working.
"Hopefully Milney will also come through with a 50 tomorrow.
"I didn't realise he hit Malinga for a six a few days ago in that [shorter] form in Sri Lanka so he's brought that into the domestic season," he said of Milne who was in the first part of the T20 and ODI tour before the two tests kicked in.
While he's had a good run against the Volts, Nethula said today would be another day and he would have to start from scratch with the ball should Noema-Barnett chuck it to him.
Volts skipper Derek de Boorder, sporting a poker face, felt Otago played well and had the upper hand with a few early wickets in the first session.
"Carl Cachopa batted well and took that away from us so we probably didn't bowl as well as we'd have liked to in the last two sessions."
De Boorder said Nethula and Milne had also established themselves so the onus was on his bowlers to take advantage with good lengths on a new day today.
"If we can get a couple of wickets early then it'll bring us back into the game."
He felt with a green tinge on a strip, that traditionally flattened out, offered some swing and was the right choice but they had failed to capitalise.
"If we had taken a couple more wickets it would have been a different story."
Luke Ronchi's century put Wellington in a strong position on the first day against Auckland at Eden Park's outer oval.
Dannevirke-born ex-Australian international Ronchi struck 127 after bringing up his century off 104 balls.
Wellington were 380 all out, with Jesse Ryder, at No 4, adding a quick-fire 72 off 66 balls.