The Trimsamsa is the one division whose parts are not equal. A sign is cut into five arcs of 5, 5, 8, 7 and 5 degrees, assigned to the five non-luminous planets - Mars, Saturn, Jupiter, Mercury and Venus - and rendered as their own signs, with the whole order reversed in an even sign. Brihat Parashara Hora Shastra ch. 6 assigns the D30 to character and misfortunes.
In an odd sign the arcs run: 0 to 5 degrees to Mars, shown as Aries; 5 to 10 to Saturn, shown as Aquarius; 10 to 18 to Jupiter, shown as Sagittarius; 18 to 25 to Mercury, shown as Gemini; and 25 to 30 to Venus, shown as Libra. In an even sign the same five are taken in reverse: 0 to 5 to Venus as Taurus, 5 to 12 to Mercury as Virgo, 12 to 20 to Jupiter as Pisces, 20 to 25 to Saturn as Capricorn, and 25 to 30 to Mars as Scorpio.
Two things follow from that table. The Sun and the Moon never appear as D30 destinations, because the division is built on the five non-luminous planets only; and a D30 placement always lands in one of ten signs, never in Cancer or Leo. Both are structural facts about the scheme, useful for checking a result.
A second construction is in use, and AstroZivi ships it rather than pretending the sources agree. The Parivritti Trimsamsa divides the sign into thirty equal parts of one degree and cycles them continuously through the zodiac, which makes all twelve signs reachable and removes the unequal arcs entirely.
This page computes the Parashari unequal scheme, which is the BPHS one. The full divisional-charts tool lets you switch to the Parivritti version and labels each with its own note. Where two published constructions give different signs for the same planet, the site's practice is to expose the choice rather than to bury it.
BPHS ch. 6 gives the D30 the subject of character and of the misfortunes or evils indicated in a chart. In practice it is read as a refinement of the analysis of weaknesses, beside the 6th, 8th and 12th houses of the birth chart, rather than as a source of independent predictions.
AstroZivi names that subject and computes the division precisely. It does not print a character reading from a D30 placement: that would need a named text and verse behind each statement, and the site holds every reading to that bar. What the page states exactly is which arc a planet falls in, which sign that arc renders as, and the resulting house and dignity.
For educational purposes. Astrological interpretations are traditional and not a substitute for professional advice.