Galvanometers frontplate symbols

Measurement type

symbol	meaning
	Direct current circuit and/or d.c. responding measuring element
	Alternating current circuit and/or a.c. responding measuring element
	Direct and/or alternating current circuit and/or d.c.and a.c. responding measuring element
	Three-phase alternating current circuit (general symbol)
	One measuring element (E) for three-wire network
	One measuring element (E) for four-wire network
	Two measuring elements (E) for three-wire network with unbalanced loads
	Two measuring elements (E) for four-wire network with unbalanced loads
	Three measuring elements (E) for four-wire network with unbalanced loads

Safety

symbol	meaning
	Earth (ground) terminal
	Protective conductor terminal
	Frame or chassis terminal
	Equipotentiality
	On (Power)
	Off (Power)
	Equipment protected throughout by double insulation or reinforced insulation
	Caution, possibility of electric shock
	Caution, hot surface
	In position of a bi-stable push control
	Out position of a bi-stable push control

Position of use

symbol	meaning
	Instrument to be used with the dial vertical
	Instrument to be used with the dial horizontal
	Instrument to be used with the dial inclined (e.g. 60°) from the horizontal plane
	Example for instrument to be used as D-1, nominal range of use from 80° to 100°
	Example for instrument to be used as D-2, nominal range of use from –1° to +1°
	Example for instrument to be used as D-3, nominal range of use from 45° to 75°

Accuracy class

symbol	meaning
	Class index (e.g. 1) except when the fiducial value corresponds to the scale length or the indicated value or the span
	Class index (e.g. 1) when the fiducial value corresponds to the scale length
	Class index (e.g. 1) when the fiducial value corresponds to the indicated value
	Class index (e.g. 1) when the fiducial value corresponds to the span

General symbols

symbol	meaning
	Permanent-magnet moving-coil instrument
	Permanent-magnet ratiometer (quotientmeter)
	Moving permanent-magnet instrument
	Moving permanent-magnet ratiometer (quotientmeter)
	Moving-iron instrument
	Polarized moving-iron instrument
	Moving-iron ratiometer (quotientmeter)
	Ironless electrodynamic instrument
	Iron-cored electrodynamic (ferro-dynamic) instrument
	Ironless electro-dynamic ratiometer (quotientmeter)
	Iron-cored electro-dynamic (ferro-dynamic) ratiometer (quotientmeter)
	Induction instrument
	Induction ratiometer (quotientmeter)
	Bimetallic instrument
	Electrostatic instrument
	Vibrating-reed instrument
	Non-insulated thermocouple (thermal converter)
	Insulated thermocouple (thermal converter)
	Electronic device in a measuring circuit
	Electronic device in an auxiliary circuit
	Rectifier
	Shunt
	Series resistor
	Series inductor
	Series impedance
	Electric screen
	Magnetic screen
	Astatic instrument
	Magnetic field strength expressed in kiloamperes per metre, producing a variation corresponding to the class index (e.g. 2 kA/m)
	Zero (span) adjuster
	Refer to a separate document
	Electric field strength expressed in kilovolts per metre, producing a variation corresponding to the class index (e.g. 10 kV/m)
	General accessory
	Ferrous support of thickness X mm
	Ferrous support of any thickness
	Non-ferrous support of any thickness
	Noiseless earth (ground) terminal
	Signal low terminal
	Positive terminal
	Negative terminal
	Resistance range setting control
	Overload protection device fitted
	Overload protection device reset control

Groups of environmental conditions

symbol	meaning
	Instrument used in laboratory
	Instrument used outdoor or under conditions that the ambient temperature changes badly

Testing voltage

symbol	meaning
	Tested voltage, up to 500V
	Tested voltage, up to 2kV
	No test

Examples

From left to right:

• Direct and/or alternating current circuit and/or d.c.and a.c. responding measuring element
• Tested up to 2kV
• unknown
• Instrument to be used with the dial vertical
• Moving-iron instrument