Was fixing a bad wiring job between a sub panel and a 240v 2 phase water pump and noticed that my multimedia was only testing it as 190v. Checked back at the breaker and saw the same. Checked between L1 and L2 on a different breaker and saw the same.
My 240v equipment (dryer, oven, water heater, 2 HVAC units) all work fine.
Should I be concerned?
How big of a deal is this? Like call an electrician asap or wait until I have some other electrical work lined up?
Standard is for US buildings to be supplied with 240v center-tapped (single-family), 208Y120 3-phase (light commercial/multifamily), or 480Y277 3-phase (large commercial, light industrial).
120V is never supplied on its own.