The PSLV-C40 mission is scheduled to be launched at 9.28am on Friday at Satish Dhawan Space Centre, Sriharikota.
The 28 worldwide customer satellites are being launched as part of the commercial arrangements between ISRO and Antrix Corporation Ltd., a company under Department of Space.
The co-passenger satellites consist of one microsatellite and one nanosatellite from India, as well as 3 microsatellites and 25 nanosatellites from Canada, Finland, France, South Korea, UK and USA.
The 144-foot-tall (44-meter) PSLV set for launch Friday will deliver India's Cartosat 2F mapping satellite to orbit, along with 30 secondary payloads for Indian, U.S., South Korean, British, French, Canadian, and Finnish customers.
The 31 satellites with a combined weight of 1,323 kg have been integrated with the PSLV for deploying them in the earth's lower orbit after lift off.
The satellite will be launched shortly. India, too, is sending one micro and nano satellite.
Today's launch comes after the unsuccessful mission of navigation satellite IRNSS-1H in 2017.
Isro's trusted workhorse PSLV will carry the weather observation "Cartosat-2" series satellite and 30 co-passengers at lift-off.
Based on information provided by ISRO, the Cartosat 2 series satellite is the third satellite in the Cartosat series which is made with the objective of providing high-resolution scene-specific spot imagery which will be used for Land Information System (LIS) as well as Geographical Information System (GIS)-based applications. It will boost data services for urban and rural applications, coastal land use and regulation, monitoring of road networks, water distribution, and land-use mapping, said an HT report. The satellite didn't come out of the heat shield as it should have, though the PSLV rocket's lift off was as planned.