If the UPS system has two parallel rectifiers, the normal operation shall be that both rectifiers are working in parallel supplying the DC load and in addition float charging the battery. If one rectifier fails then the remaining rectifier shall be rated to supply the total DC load and its own battery float charge requirements. Parallel rectifier units shall be designed so that during parallel operation, load sharing shall occur. The difference between the rectifiers DC current shall not exceed 10 % of the rated current for one rectifier.3.14 Static transfer switch SR-41605 - In case of inverter failure, the static transfer switch shall transfer the load from the inverter to the bypass circuit. The monitoring circuits shall be designed to minimise spurious operations due to load changes and other transient conditions.SR-41606 - If the UPS switches over to the bypass supply due to inverter failure, the logic shall lock out the inverter and shall not automatically transfer back to the inverter supply. No-break return to the inverter supply shall be manually initiated.