MDI-96(3)
MDI-72
Beemet maximum demand indicator meters indicate the thermal /time characteristics of load and help audit efficient use of transformer stations and LT distribution feeders. The dimensions comply with the requirements of DIN 43700 and scales with DIN 43802. The performance confirms to IS 1248-83/93. The cases are made of polycarbonate.
The instrument pointer is accompanied by a red slave pointer which is driven by the torque of a bimetallic movement. This slave pointer remains at the max reading position for a successive reading and has to be reset to its default position with the help of a knob.
In the three-pointer MDI meter, a moving iron movement is housed in addition to the bimetallic spring, which indicates instantaneous and maximum demand currents.
Salient Features
• Rugged movement ensures sustained accuracy and reliability.
• Reset knob is easily accessible.
• Square bezel permits edge to edge mounting, allowing maximum use of panel space.
• Interchangeable dial for range portability.
• Almost linear scale for MI dial in 3-pointer.
• Clear scaling for easy reading.
General Specifications
| Accuracy | ±3.0% FSD (Bimetallic), ±1.5% FSD (Moving Iron) |
| Measurable Quantities | AC Current |
| Pointer deflection | 0 - 90º |
| Frequency | 45 – 60Hz |
| Thermal Time delay | 8 or 15 minutes |
| Moving Iron Response Time | ~2 seconds |
| Overload capacity | According to IS: 1248 / IEC 51 |
| Short duration | 10 times for 5s: 1 overload 10 times for 0.5s: 9 overload |
| Continiously | 1.2 times rated voltage or current |
| Power Consumption @1A | <1.6VA (2-pointer), <2.5VA (3-pointer) |
| Power Consumption @5A | <2.5VA (2-pointer), <3.4VA (3-pointer) |
| Ambient Temperature @ use | 0 to 50°C |
| Operating Temperature | -10 to 55°C |
| Storage Temperature | -25 to 65°C |
| Relative Humidity | < 75% annual average, non-condensing |
Range Chart
| Model | Bimetallic | Moving Iron | For use on CT |
|---|---|---|---|
| MDI – 72, 96(3) | 1A | 1A | __ / 1A |
| MDI – 72, 96(3) | 5A | 5A | __ / 5A |
Dimensions
| Pointers | Model | Dimensions (mm) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| A | B | C | D | E | Bimetallic Scale | Moving Iron Scale | Panel Cutout | |||
| Two Pointers | MDI-72 | 72 | 66 | 53 | 67.3 | 5.5 | 61 | – | 68x68 | |
| MDI-96 | 96 | 90 | 53 | 91.5 | 5.5 | 97 | – | 92x92 | ||
| Three Pointers | MDI-72(3) | 72 | 66 | 53 | 67.3 | 5.5 | 52 | 61 | 68x68 | |
| MDI-96(3) | 96 | 90 | 53 | 91.5 | 5.5 | 71 | 97 | 92x92 | ||
Wiring Diagrams
