The pointer type frequency meters, FM 48/72/96/144 are housed in molded polycarbonate cases are suitable for the measurement of frequencies in the range of 45 to 450 Hz. For maximum accuracy, the essential measuring range is obtained by suppressing the unwanted frequency span. These instruments offer several advantages in switchboard and generating set panels. A number of meters can be mounted in a panel cut out (mosaic mounting). The front glass, bezel, and dial can be easily replaced.
| Features | • Linear Scale |
|---|---|
| Functional Principle | Frequencies are measured with a built-in electronic transducer and moving coil indicator. Moving coil movement has pivots of very high hardness. Movement is suspended between spring-loaded sapphire jewels. Movement is properly shielded and critically damped by eddy currents induced in coil former. |
| Case Options | • Antiglare glass front fascia |
| Dial Options | • Blank dial with initial and end values marked |
Mechanical
| Case Details | Molded square suitable for mounting in control switchgear panels and machinery consoles. |
| Case material | Polycarbonate, flame retardant, and drop proof per UL 94-V-0 |
| Front Fascia | Glass |
| Color of Bezel | Black |
| Position of Use | Vertical |
| Panel Fixing | Mounting clamps |
| Mounting | Stackable in a single cutout |
| Panel Thickness | ≤25mm |
| Terminals | Hexagon studs, M4, screws, and wire clamps, E3. |
Electrical
| Measured Quantity | Frequency |
| Input Quantity | Alternating voltage in the sine waveform |
| Power Consumption | <7Va |
| Overload Capacity | Acc to IS: 1248/IEC 51 |
| Continuously | 1.2 times rated voltage/current |
| Short Duration | 2 times rated voltage for 0.5 seconds: 9 overloads 2 times rated voltage for 5 seconds: 1 overloads |
| Enclosure Code (IEC 529) | IP 52 - case cover IP00 - terminals without back cover IP20 - terminals with back cover |
| Insulation Class | Group A according to VDE 0110 |
| Rated Insulation Voltage | 660V |
| Proof Voltage | 2KV |
| Insulation Category | 300V CAT III |
| Insulation Resistance | <50MΩ at 500 Vdc |
Scale & Pointer
| Model | FM48 | FM72 | FM96 | FM144 |
| Scale Length | 41mm | 63mm | 97mm | 146mm |
| Scale Characteristics | Linear | |||
| Scale Division | Coarse - Fine | |||
| Pointer | Knife edge | |||
| Pointer Deflection | 0-90° | |||
Environmenal
| Climatic Suitability | Climate category II as per IS:1248, IEC 60051 Climatic class III according to VDE/VDI 3540 |
| Operating Temperature | -10° to +55°C |
| Storage Temperature | -25° to +65°C |
| Relative Humidity | ≥75% annual average, non-condensing |
| Shock Resistance | 15gn for pulse duration 11ms |
| Vibration Resistance | 10-55-10 Hz for amplification 0.15mm (1.5g at 50Hz) |
| Pollution Degree | 2 |
| IS 2419 DIN IEC 61554 | Nominal case and cutout dimensions for indicating electrical instruments |
| IS 1248 DIN 43802 | Scale and pointer for electrical measuring instruments |
| IS 1248 DIN 43807 | Connections and terminal markings for panel meters |
| DIN 46200 DIN 46282 | Terminal bolts/leads |
| DIN 46282 | Clamp straps for connections |
| IS 9249 DIN 40050 | Safety requirements and protective measures for electrical indicating. |
| VDE 0110 VDE 0410 IEC 529 IEC 1010 | Instruments and their accessories. |
| IS 1248 IEC 51/DIN EN 60051 DIN 43701 | Performance specifications for direct acting indicating analog electrical measuring instruments and their accessories. |
| IS 1248 IS 9000 VDE/VDI 3540 | Environmental condition |
| DIN 43718 | Front frames for indicating measuring instruments principle dimensions |
| UL 94-V-0 | UL combustibility class |
| DIN 43701 | Technical conditions for delivery of electrical instruments |
| Is 1248/IEC 51 IS 9000 VDE 0411 IEC 61010 | Mechanical strength (free-fall test, vibration test) |
European Compliances
| 2004/108/EC | EMC directive |
| 2006/95/EC | Low voltage directive |
| Amendment 93/68/EEC | For CE marking |
| Datasheet |
| IS 2419 DIN IEC 61554 | Nominal case and cutout dimensions for indicating electrical instruments |
| IS 1248 DIN 43802 | Scale and pointer for electrical measuring instruments |
| IS 1248 DIN 43807 | Connections and terminal markings for panel meters |
| DIN 46200 DIN 46282 | Terminal bolts/leads |
| DIN 46282 | Clamp straps for connections |
| IS 9249 DIN 40050 | Safety requirements and protective measures for electrical indicating. |
| VDE 0110 VDE 0410 IEC 529 IEC 1010 | Instruments and their accessories. |
| IS 1248 IEC 51/DIN EN 60051 DIN 43701 | Performance specifications for direct acting indicating analog electrical measuring instruments and their accessories. |
| IS 1248 IS 9000 VDE/VDI 3540 | Environmental condition |
| DIN 43718 | Front frames for indicating measuring instruments principle dimensions |
| UL 94-V-0 | UL combustibility class |
| DIN 43701 | Technical conditions for delivery of electrical instruments |
| Is 1248/IEC 51 IS 9000 VDE 0411 IEC 61010 | Mechanical strength (free-fall test, vibration test) |
European Compliances
| 2004/108/EC | EMC directive |
| 2006/95/EC | Low voltage directive |
| Amendment 93/68/EEC | For CE marking |
