# Plasma arc-voltage: polarity, brown +, pin 1/2 on P-metalwise/85

- Source-Date (SAST): 2023-04-20 17:26
- From/To: April → support
- Dest: both
- Review-after: 2027-02-28
- Status: current
- Source: company email (Archives/Internal Affairs), 2023-04-20

## Facts

- Arc-voltage from the plasma unit is **polarised** — do not reverse.
- Loom is usually **blue / brown**; **brown is positive**. If colours differ, open the THC and check.
- Wrong polarity **blows the resistor**; symptom on the plasma is **arc break**. Bypass exists if blown.
- **P-metalwise/85** box accessory plug: connector **1 = positive**, **2 = negative**.