Does anyone know what the letters on the power plug mean?

n stands for fire, L for zero, and the other for ground Yes, electricians know this, and I agree with the 2nd floor

Ammeter PA

Voltmeter PV

Active meter PJ

Reactive meter PJR

Frequency meter PF

Phasor meter PPA

Maximum demand meter (Load monitoring meter) PM

Power Factor Meter PPF

Active Power Meter PW

Reactive Power Meter PR

Reactive Current Meter PAR

Acoustic Signal HA

Light Signal HS

Indicator HL

Red Light HR

Green Light HG

Yellow Light HY

Blue Lamp HB

White Lamp HW

Connection Lug XB

Plug XP

Socket XS

Terminal Block XT

Wire, Cable, Busbar W

Direct Current Busbar WB

Plug-In (feeder) Busbar WIB

Electric Power branch WP

Lighting branch WL

Emergency lighting branch WE

Power trunking WPM

Lighting trunking WLM

Emergency lighting trunking WEM

Slip contact WT

Closing mini-bus WCL

Control mini-bus WC

Signal mini-bus WS

Signal mini-bus WS

Control mini-bus WC

Signal mini-bus WC

Signal mini-bus WS

Signal mini-bus WS

Flashing mini-bus WF

Accident sound mini-bus WFS

Forecast sound mini-bus WPS

Voltage mini-bus WV

Accident lighting mini-bus WELM

Lightning arrester F

Fuse FU

Fast fuse FTF

Dropping fuse FF

Voltage limiting protection device FV

Capacitor C

Power capacitor CE

Forward button SBF

Reverse button SBR

Stop button SBS

Emergency button SBE

Test button SBT

Reset button SR

Limit switch SQ

Proximity switch SQP

Manual control switch SH

Time control switch SK

Level control switch SL

Humidity control switch SM

Pressure control switch SP

Speed control switch SS

Temperature control Switches, auxiliary ST

Voltmeter diverter switch SV

Ammeter diverter switch SA

Rectifiers U

Silicon controlled rectifiers UR

Rectifiers with power supply for control circuits VC

Inverters UF

Converters UC

Inverters UI

Motor M

Asynchronous Motor MA

Synchronous Motor MS

Direct Current Motor MD

Wound Rotor Induction Motor MW

Squirrel Cage Motor MC

Electromagnetic Valve YM

Solenoid Valve YV

Fire Damper YF

Smoke Evacuation Valve YS

Solenoid locks YL

Tripping coils YT

Closing coils YC

Pneumatic actuators YPA,YA

Electric actuators YE

Heating devices (electric heating) FH

Lighting lamps (luminous devices) EL

Air conditioners EV

Electric heater heating Components EE

Induction coils, reactors L

Excitation coils LF

Arc-canceling coils LA

Filter capacitors LL

Resistors, varistors R

Potentiometers RP

Thermistors RT

Photosensitive resistors RL

Voltage-sensitive resistors RPS

Grounding Resistor RG

Discharge Resistor RD

Starting Resistor RS

Frequency Sensitive Resistor RF

Current Limiting Resistor RC

Photocells, Thermoelectric Sensors B

Pressure Transformer BP

Temperature Transformer BT

Velocity Transformer BV

Time measurement sensors BT1,BK

Level measurement sensors BL

Temperature measurement sensors BH,BM