Most Ophir power meters use a 12 VDC power supply with an industry standard 5.5 mm plug that supplies a minimum of 500 mA to the meter. This power supply is reverse voltage to many US products, meaning the outside connection is positive (+) and the inside is negative (-). When connecting a power supply to the Ophir power meter, make sure that the power supply is a 12 VDC power supply with minimum 500 mA and that the center is negative (-). Some of the newer Ophir power meters like the Vega, Quasar and latest version of the Nova-II are dual polarity compatible meaning it does not matter if the power supply is center positive or center negative. It still needs to be 12 VDC and minimum 500 mA, but it can be either a center positive or center negative. In addition, most Ophir power sensors which include fans for cooling use the same type of power supply with inside connection negative (-).
The exception to this is the StarLite meter which uses a different type of power supply. The StarLite requires a 12 VDC power supply capable of supplying at least 15 W (1.25 A) to the meter, and uses a 3.5 mm plug. The polarity is inside connection positive (+).
In all cases, it is highly recommended that the original power supply included with the equipment be used and if it is missing that Ophir be contacted for a replacement supply.