Wright wasted no time in securing Iwelumo after failing in a loan move for Blackburn Rovers' David Goodwillie, who is being tracked by Oldham Athletic.
"Chris has signed through to the end of the season with scope for playing his way into a longer stay here," Wright said. "I have been looking for presence in that area of the team and Chris is a powerful striker and holds the ball up well. He could be a very good foil for Stevie May at a crucial time of the season. He certainly isn't here as a replacement for Stevie. He could also give Stevie a breather at certain times during games.
"He may be 35 but he is fit and in great condition. He will add a different dimension to us."
St Johnstone have told Peterborough United, the club who are interested in May, that they are nowhere near the club's valuation.
Steve Brown, the chairman at McDiarmid Park, stressed the Sky Bet League One club had yet to make a formal bid at all, although he admitted discussions had taken place over the 21-year-old who has already scored 20 goals this season.
There is some wariness between the two clubs after a public fall-out when Peterborough made two failed attempts to sign May in August.
At that point Peterborough insisted they would not return, and made a series of disparaging public comments about St Johnstone's handling of the talks, but this week they went back on their word by renewing their interest in May.
St Johnstone would look for around £1m for May but Brown said Peterborough had come nowhere near that in any of the discussions this week. Peterborough's director of football, Barry Fry, claimed to have submitted two bids in the current window and said the most recent one would be their final offer. The reported figure was £500,000 rising to a possible £1m with add-ons.
But Brown said: "These figures have grown arms and legs. What he would term as a bid and what I would term ongoing discussions are somewhat different in my eyes. But the figures being talked about are not acceptable to us anyway. The bottom line is they haven't met our valuation. I don't know if they will be back in. They might or they might not."
Wright has conceded that if any buying club meets St Johnstone's valuation, and May himself is happy to leave, a deal will be done. The club is also is close to adding both a striker and a midfielder. "We are almost there but in a transfer window there are so many plates spinning," said Brown. "It's crazy, someone has to move out before someone can move in. Every club's the same."
And Wright later made it clear he believes May should be setting his sights higher than League One when he does decide to finally move on.
"We are consistent," Wright said. "Until our valuation is met he will remain our player. And even if a club meets our valuation it will be down to Stevie May.
"No one is going to get Stevie May on the cheap. That won't happen. He will go eventually and for the market value. He may or may not attract clubs from the Championship or even the Premiership. He just has to keep playing and scoring goals. He is on target now hopefully to get 30 goals and that should create even more interest in him."
There was positive news for St Johnstone yesterday when the Scottish Football Association downgraded Steven Anderson's red card against Hearts last weekend to a caution. Anderson had claimed that referee Brian Colvin was wrong to dismiss him for denying Dale Carrick a goalscoring opportunity. Carrick was moving wide and 30 yards out when Anderson tackled him.
The claim was upheld by Judicial Panel which decided the appropriate sanction was a yellow card for deliberately playing an opponent's legs.