*J

Here’s a list of Instrumentation abbreviations starting with the letter “J”, commonly used in P&IDs, datasheets, control systems, and field instrumentation.

J: Junction / Jack / Joint (context dependent)
JA: Junction Assembly / Junction Alarm
JAC: Junction Alarm Controller
JAM: Junction Alarm Module
JB: Junction Box
JBC: Junction Box Controller
JBD: Junction Box Device
JC: Junction Controller / Joint Controller
JCC: Junction Control Cabinet
JCD: Junction Control Device
JCM: Junction Control Module
JCP: Junction Control Panel
JCS: Junction Control System
JD: Junction Device
JE: Junction Enclosure
JF: Junction Filter / Jack Female
JG: Junction Ground
JH: Junction Heater
JI: Junction Indicator / Jack Input
JIC: Junction Indicating Controller
JIM: Junction Interface Module
JL: Junction Level / Joint Level
JM: Junction Module / Jack Module
JMC: Junction Module Controller
JN: Junction Node
JO: Junction Output / Jack Output
JOC: Junction Output Controller
JOM: Junction Output Module
JP: Junction Point / Jack Panel
JPC: Junction Panel Controller
JPD: Junction Pressure Device
JPI: Junction Pressure Indicator
JPT: Junction Pressure Transmitter
JR: Junction Relay
JRC: Junction Relay Controller
JRD: Junction Relay Device
JS: Junction Switch / Jack Switch
JSC: Junction Switch Controller
JSD: Junction Shutdown Device
JT: Junction Transmitter / Jack Transmitter
JTC: Junction Temperature Controller
JTD: Junction Trip Device
JTI: Junction Temperature Indicator
JTT: Junction Temperature Transmitter
JV: Junction Valve / Jack Valve
JVC: Junction Valve Controller
JVM: Junction Valve Module