For multivalent ions, it is usual to consider the conductivity divided by the equivalent ion concentration in terms of equivalents per litre, where 1 equivalent is the quantity of ions that have the same amount of electric charge as 1 mol of a monovalent ion:  mol Ca2+,  mol ,  mol Al3+,  mol , etc.
For ions with multiple valencies, it's customary to calculate conductivity in terms of equivalents per liter, where 1 equivalent corresponds to the amount of ions having the same electric charge as 1 mole of a monovalent ion: moles Ca2+, moles , moles Al3+, moles , etc.