Analog measuring accessories
Analog measurement accessories include mounting brackets, voltmeter and ammeter switches, as well as connection…
Analogue measurement accessories are the essential complementary equipment for mounting and connecting analogue measuring instruments in an electrical panel. They include front-face mounting supports, phase-selector switches and dedicated connection terminals. These elements ensure compatibility with devices compliant with the IEC 60051 standard and help reduce panel space by sharing instruments.
Types of accessories for analogue measuring instruments
Front-face mounting supports for ammeters and voltmeters
Mounting supports ensure the mechanical installation of analogue measuring devices on panel doors or front panels. Our installation experience confirms that the mechanical stability of these supports determines the long-term readability of the graduated scales. The plastic housing of the accessories provides insulation suited to standard panel environments.
Voltmeter and ammeter phase-selector switches
Voltmeter and ammeter selector switches alternately direct the signals of the three phases to a single analogue measuring device. This feature significantly reduces the number of instruments needed on the panel's front face. Feedback from installers confirms that this solution is particularly appreciated in tertiary distribution enclosures where available space is limited. The copper contacts of the switches provide reliable electrical conductivity and durable connections.
Connection terminals dedicated to measurement circuits
Connection terminals form the electrical interface between secondary measurement circuits and analogue instruments. They make wiring and later maintenance of installations easier. We recommend checking the compatibility of conductor sections with the terminals' clamping capacity when choosing accessories.
Applications and value of analogue measurement accessories
Multi-phase measurement with a single analogue instrument
Phase selection for multi-phase analogue measurement is the main application of the switches associated with voltmeters and ammeters. A single device successively displays the values of the three phases, simplifying monitoring of three-phase networks. Our standard practice favours this configuration for secondary distribution panels where simultaneous permanent monitoring of each phase is not required.
Mounting measuring devices on the panel front face
Mounting measuring devices on a panel front face requires coordination between the flush-mount dimensions, the mounting supports and the connection terminals. Analogue measurement accessories standardised to IEC 60051 ensure this mechanical and electrical interoperability. In the field, we find that harmonising these elements reduces mounting time and limits wiring errors.
Normative compatibility and material choices
IEC 60051 compliance for instruments and associated accessories
The IEC 60051 standard defines the requirements applicable to direct-indicating analogue measuring devices and their mounting accessories. This normative compatibility guarantees dimensional and electrical consistency between instruments and fixing, switching and connection elements. Our commissioning tests show that meeting this standard avoids fitting problems when replacing instruments during maintenance.
Material characteristics of measurement accessories
The plastic housing of the supports and switches offers resistance to atmospheric agents commonly found in electrical panel environments. The copper contacts of voltmeter and ammeter switches have low electrical resistivity, limiting heating and voltage drop in measurement circuits. We observe that the combination of these materials meets the demands of continuous use in fixed installations.
Frequently asked questions
What is the difference between a voltmeter switch and an ammeter switch?
The voltmeter switch selects the phase voltages to be measured on an analogue voltmeter, while the ammeter switch switches the phase currents to a single ammeter. Their operating principle is identical, but their internal circuit and withstand rating are adapted respectively to voltage and current circuits.
Can a phase switch be installed on an already-existing measuring device?
Installing a phase switch requires checking mechanical and electrical compatibility with the existing instrument. The flush-mount dimensions, terminal type and measurement range must match the selected switch's specifications.
Does the IEC 60051 standard apply only to instruments or also to accessories?
The IEC 60051 standard mainly concerns direct-indicating analogue measuring devices, but the compatibility of accessories with this standard ensures their mechanical and electrical interoperability with compliant instruments.
What space saving is achieved with a phase switch?
A phase switch allows three measuring instruments to be replaced with a single one, reducing the area occupied on the panel front face for three-phase measurement by around two-thirds.