Two alternative options, you could try:

• Formula used in cell B2

=SUM(IFERROR(MID("0"&A2,SEARCH({"d","h","m","s"},A2)-1,2),0)*{"1","1:0","0:1","0:0:1"})*86400

Or,

• Formula used in cell C2

=SUM(IFERROR(MID(0&A2,SEARCH({"h","m","s"},0&A2)-2,2),{0,0,0})*{3600,60,1})

And in D2

=B2/24/60/60

Format cells as [h]:mm:ss;@

Two alternative options, you could try:

• Formula used in cell B2

=SUM(IFERROR(MID("0"&A2,SEARCH({"d","h","m","s"},A2)-1,2),0)*{"1","1:0","0:1","0:0:1"})*86400

Or,

• Formula used in cell C2

=SUM(IFERROR(MID(0&A2,SEARCH({"d","h","m","s"},0&A2)-2,2),{0,0,0,0})*{86400,3600,60,1})

And in D2

=B2/24/60/60

Format cells as [h]:mm:ss;@

Two alternative options, you could try:

• Formula used in cell B2

=SUM(IFERROR(MID("0"&A2,SEARCH({"d","h","m","s"},A2)-1,2),0)*{"1","1:0","0:1","0:0:1"})*86400

Or,

• Formula used in cell C2

=SUM(IFERROR(MID(0&A2,SEARCH({"h","m","s"},0&A2)-2,2),{0,0,0})*{3600,60,1})

And in D2

=B2/24/60/60

Format cells as h:m:ss

Two alternative options, you could try:

• Formula used in cell B2

=SUM(IFERROR(MID("0"&A2,SEARCH({"d","h","m","s"},A2)-1,2),0)*{"1","1:0","0:1","0:0:1"})*86400

Or,

• Formula used in cell C2

=SUM(IFERROR(MID(0&A2,SEARCH({"h","m","s"},0&A2)-2,2),{0,0,0})*{3600,60,1})

And in D2

=B2/24/60/60

Format cells as [h]:mm:ss;@