Blue Sea Systems DC Zero Center Analog Ammeter with Shunt, 2.75in Face, 50mV External Shunt, Backlit Meter Face

Overview

The Blue Sea Systems DC Zero Center Analog Ammeter is a panel-mounted DC current meter for monitoring charge and discharge current on a boat battery or DC distribution system. Its zero-center scale lets the needle move in either direction, so the operator can see whether current is flowing into the battery bank from charging equipment or out of the bank to onboard loads.

This analog ammeter uses an external 50 mV shunt and a 2.75 in (69.85 mm) meter face. The meter draws its sensing power from the shunt connection, while the backlit face uses separate 12V or 24V DC backlight connections with low current draw of 16 mA at 12V DC or 20 mA at 24V DC.

It suits helm stations, DC electrical panels, battery switch areas, and nav stations where a simple visual current reference is easier to read at a glance than a digital display. The included shunt keeps the high-current cable run at the shunt location, leaving the meter to be wired as a remote display in the panel.

Key features

• Zero-center analog scale reads both discharge and charge current on DC systems.
• 2.75 in (69.85 mm) face size fits common marine electrical panel layouts.
• External shunt setup uses a 50 mV full-scale signal for remote current measurement.
• Meter senses and powers itself from the shunt connection, with separate wiring only for the optional backlight.
• Backlit face supports 12V or 24V DC backlight circuits for easier viewing in low light.
• Available in 50-0-50A and 100-0-100A ranges to match different DC load and charging profiles.
• Includes the matching DC shunt for the selected amperage range.

Variants

This ammeter is offered in two current ranges. Both variants use the same 2.75 in face format, zero-center DC display style, external 50 mV shunt type, and 12V or 24V DC backlight connection.

The amperage range and included shunt change by variant, so the selected version should match the expected current flow in the circuit being monitored.

• 8252: 50-0-50A amperage range. This range is suited to lower-current DC circuits or smaller battery systems where charge and discharge current normally stays within a 50A scale.
• 8253: 100-0-100A amperage range. This range gives more scale capacity for larger DC loads, higher-output charging sources, or battery systems that can see current movement above 50A.

Installation and setup

The shunt should be installed in the monitored DC circuit where it can safely measure current flow, while the meter face can be mounted in a visible panel location. This layout is useful on boats because the heavy current path can remain near the battery or distribution equipment instead of being routed through the instrument panel.

For the zero-center reading to make sense, shunt orientation and meter wiring should follow the intended charge and discharge direction. The backlight can be tied into the vessel lighting circuit when night readability is needed at the helm, nav station, or electrical panel.

Compatibility and fit

This product is for DC current monitoring and is not a replacement for a battery monitor that calculates state of charge, amp-hours, or battery history. It is a good match for boat owners who want a direct analog view of current flow from alternators, chargers, solar charging equipment, or onboard DC loads.

What’s included

• DC zero center analog ammeter
• Matching DC shunt for the selected amperage range