Product Overview
The F48D-BMΩ Dual-Channel AC Insulation Monitor is an instrument designed to monitor and provide alarms regarding poor grounding conditions within a ship's AC power grid. This device is utilized to continuously monitor the insulation resistance between the ship's hull and the electrical circuits within ungrounded AC power distribution systems operating at voltages of 500V or less. It issues audible and visual alarm signals whenever an anomaly occurs in the grid's insulation resistance—specifically, when the resistance drops below the alarm threshold configured on the instrument. The effective measurement range of this device spans from 0.005 MΩ to 5 MΩ, with five selectable alarm threshold settings: 50 kΩ, 200 kΩ, 300 kΩ, 500 kΩ, and 1000 kΩ. Other custom alarm values are also available upon request. (Manufactured by Anhang Electric). The external alarm signal output terminals feature a contact capacity of DC 24V/3A or AC 220V/1A, providing dual-channel alarm signal output capabilities.
Specifications
F48D-BMΩ Dual-Channel AC Insulation Monitor
This instrument is designed to monitor and provide alarms regarding poor grounding conditions within a ship's AC power grid.
The device is used to continuously monitor the insulation resistance between the ship's hull and the electrical circuits within ungrounded AC power distribution systems operating at voltages of 500V or less. It issues audible and visual alarm signals whenever an anomaly occurs in the grid's insulation resistance—specifically, when the resistance drops below the alarm threshold configured on the instrument.
The effective measurement range of this instrument is 0.005 to 5 MΩ. It features five selectable alarm thresholds: 50 kΩ, 200 kΩ, 300 kΩ, 500 kΩ, and 1000 kΩ. Custom alarm thresholds are also available upon request. (Anhang Electric)
The output capacity for external alarm signals is rated at DC 24V/3A or AC 220V/1A. The unit provides dual-channel alarm signal outputs.
Once properly wired and powered on, the power indicator light will illuminate, signifying that the instrument has entered monitoring mode; the pointer indication on the meter now displays the current insulation resistance value of the power grid.
The alarm threshold can be configured as needed by adjusting the red setting pointer to the desired resistance value. Should the grid's insulation resistance drop below this set threshold, the instrument will output an alarm signal, and the corresponding alarm indicator light will illuminate. Once the insulation resistance returns to a normal level, the instrument will automatically exit the alarm state.
Within a single power network, it is strictly prohibited to operate two insulation monitors—or any other similar instruments—simultaneously to measure the insulation resistance of the same network.
To verify the proper functioning of the instrument, a self-test procedure may be performed. Upon completion of the self-test, it is imperative to return the instrument to its normal operating mode. Note: This meter measures a range of 0–5 MΩ, with a rated operating voltage of AC 220V.
Q/F96 Marine Meter Series: Overall dimensions 96 × 96 mm; Panel cutout dimensions 92 × 92 mm.
Q96, F96, 51L5 (Z96), 51C5, 51L4, 51T4, 51C4, 51T5, 51L6, 51C6, 51T6, LS96, DN96, etc.
New 45L8/L9 Marine Meter Series: Overall dimensions 110 × 110 mm; Panel cutout diameter 101 mm; Four-screw mounting dimensions 90 × 90 mm.
45L8, 45T8, 45C8, 45L9, 45T9, 45C9, LS-110, 2101, 2102, 2103, 2105, 2106, 2107, 2108, 2109, etc.
New 63L8 /L9 Marine Instrument Series: Overall dimensions 80 × 80 mm; panel cutout diameter 71 mm; four-screw mounting dimensions 64 × 64 mm.
Models: 63L18, 63C18, 63L19, 63C19, LS-80, 63L1, 63C1, 63L2, 63C2, 63L10, 63C11, 2181, 2182, 2183, 2185, 2187, 2188, 2189, etc.
Q/F72 Marine Instrument Series: Overall dimensions 72 × 72 mm; panel cutout dimensions 68 × 68 mm.
Models: Q72, F72, 61L14, 61C14, 61L13, 61T13, 61C13, LS72, etc.
Others: 63C7, 63L7, 45C3, 45L1, 45D1, 45C1, 42L1, 42C1, etc.
Other Marine Electrical Equipment: NGJ-I/-II Reverse Power Relays, JDG4-0.5 Voltage Transformers, DL-III Inductive Rudder Angle Indicators, etc.
**Structural Features:**
AC instruments are constructed by attaching a transistor rectification circuit to a standard DC meter base; consequently, the instruments feature low power consumption.
Thanks to a pointer deflection angle of 90 degrees (right-angle scale) and the use of a transparent acrylic cover, the instruments provide a wide and clear field of view for easy reading.
**Key Technical Specifications:**
Environmental Conditions: -25 to +40°C (0 to +40°C for AC instruments).
Relative Humidity: 25% to 80%.
Mechanical Resistance: High resistance to mechanical shock; operates satisfactorily under vibration conditions with an acceleration of 0.7g; capable of withstanding transport-related vibration with an acceleration of 150 m/s² at a frequency of 80–120 cycles per minute, sustained for a duration of 2 hours. Enclosure: Enclosure protection meets IP42 requirements.
Withstand Voltage: AC 50Hz, 2000V, for 1 minute.
Weight: Less than 1 kg.
Operating Position: Vertical (⊥).
