UNINTERRUPTIBLE POWER SUPPLY HAVING A LIQUID COOLING DEVICE

A cooling arrangement for cooling of electrical components hosted in a housing comprises a plate heat exchanger having plates defining first and second sets of gaps. The cooling arrangement also comprises first and second liquid cooling circuits. Liquid cooling devices in the first liquid cooling circuit absorb heat from the electrical components by receiving a first liquid directed to the first set of gaps by a pump. Heat is transferred from the first set of gaps to a second liquid in the second set of gaps of the plate heat exchanger. A pressure relief valve closes or opens to connect the first liquid cooling circuit to the second liquid cooling circuit to selectively allow the first cooling liquid to flow into second liquid cooling circuit, the pressure relief valve switching between the closed state and the open state based on a pressure in the first liquid cooling circuit.