| General Specifications |
| Accuracy |
±2% full scale (iron-vane), ±3% (rectifier) |
| Wattmeters |
±2% full scale; Compensated meters: ±3% full scale |
| Movement |
Model 57, 59, 157 Iron-vane, magnetically damped
Wattmeters: Dynamometer
All others: Annular, rectifier type, self-shielding |
| Suspension |
Pivot and jewel; "T" styles: taut band |
| Tracking |
±3% |
| Shielding |
Calibration is unaffected by magnetic panel mounting |
| Response Time |
1.5 seconds maximum |
| Overload |
(1 sec.) 10 times F.S. |
| Overload (Continuous) |
1.5 times F.S. |
| Repeatability |
2 %, tautband: .5% |
| Dial |
Sharp clear scale. Each dial arc is calibrated to track the specific type of movement used |
| Resistance |
±15% of meter impedance |
| Pointer |
Spade pointer with black, matte finish |
| Scale Length |
Models 177 & 157: 1.6" (40.6mm) |
| Models 147, 127 & 127T: 1.8" (45.7mm) |
| Models 57 & 77: 2.3" (58.4mm) |
| Models 27, 27T & 47: 2.5" (63.5mm) |
| Models 59 & 79: 3.50" (89.0mm) |
| Models 29, 29T & 49: 3.9" (99.0mm |
| Net Weight |
Models 57 & 157: 5 oz. (0.14 kg) |
| Model 127, 127T & 147: 7 oz. (0.20 kg) |
| Models 27, 27T, 47 & 59: 8 oz. (0.23 kg) |
| Models 77 & 177: 9 0z. (0.26 kg) |
| Models 29, 29T & 49: 11 oz. (0.31 kg) |
| Model 79: 12 oz. (0.34 kg) |
| Frequency Meter Specifications |
| Accuracy |
45-55 Hz ± 0.3 Hz (120V-240V) |
| 55-65 Hz ± 0.3 Hz (120V-240V) |
| 380-420 Hz ± 1.2 Hz (120V-240V) |
| Movement |
Small core magnet, self-shielding |
| Suspension |
Pivot and jewel |
| Shielding |
Calibration is unaffected by magnetic panel mounting |
| Center Scale Value |
50/60/400 Hz |
| Power Consumption |
1.6 VA |
| Warm-up Time |
5 minutes |
| Max. Input: Voltage (10 sec) |
150, 120V normal |
| 280, 240V normal |
| Dial |
Sharp clear scale. Each dial arc is calibrated to track the specific type of movement used |
| Case |
High density black plastic |
| Operating Temperature |
-4ºF to + 149ºF (-20ºC to + 65ºC) |
| Pointer |
Spade pointer with black, matte finish |
| Scale Length |
Model 187: 1.8" (45.7mm) |
| Model 89: 3.5" (89.0mm) |
| Model 87: 3.9" (99.0mm) |
| Net Weight |
Model 187: 5 oz. (0.14 kg) |
| Model 87: 8 oz. (0.23 kg) |
| Model 89: 11 oz. (0.31 kg) |