What is the proper voltage reading I should verify at the junction box?
For a 240V installation, the reading between the red and black wires (line to line) should be 220 to 240 volts. For a 208V installation, the reading between the red and black wires (line to line) should be 190 to 208 volts. Use a volt meter to verify these readings.
From the official Bosch HBL503 500 Series Single Wall Oven manual, page 7
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