# Station battery discharge-current measurement

Canonical URL: https://eloragrid.ai/symbols/station-battery-discharge-current-measurement
Publisher: Elora Grid
Updated: 2026-11-03
Lookup label: SBDM
Drawing use: Schematic
Reference families: Manufacturer

Representation: Functional block
Installation focus: substations
Input: Battery current sensor
Output: Discharge-current information

Identifies the measured battery discharge contribution to the station DC load.

## In plain English

### What this block does

Identifies the measured battery discharge contribution to the station DC load.

### A simple example

In a substation control building, the battery can support breaker trip circuits while the charger AC supply is unavailable. Supervision must identify whether the charger, battery or a downstream feeder is affected. For this reference, the drawing identifies “Battery current sensor” at the input and “Discharge-current information” at the output. Sensor polarity determines charge versus discharge sign.

### What the drawings help you do

Start at the named input: Battery current sensor. Identify its source device or document and the state represented on the drawing. Follow the named output: Discharge-current information. Cross-reference its destination and separate the command from confirmation that the equipment responded.

### Terms

- Input: Battery current sensor
- Output: Discharge-current information
- Application reference: An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.

Concept diagram: Battery current sensor → SBDM → Discharge-current information
A reading guide. The entry's original illustration and input/output facts describe this application.

- [MicroGenius S2/S4 battery charger technical manual](https://www.sens-usa.com/hubfs/Controlled%20Files/Manuals/101330_MGS_User_Manual.pdf)


## What it represents

Identifies the measured battery discharge contribution to the station DC load. A station battery system supplies protection, control and other assigned DC loads through a documented charger and distribution arrangement. Charger output, battery contribution and load distribution are related but separately monitored paths.
In a substation control building, the battery can support breaker trip circuits while the charger AC supply is unavailable. Supervision must identify whether the charger, battery or a downstream feeder is affected. For this reference, the drawing identifies “Battery current sensor” at the input and “Discharge-current information” at the output. Sensor polarity determines charge versus discharge sign.
Identify every source, protective device, isolation boundary and return. Battery capacity, DC fault duty, charging settings and ventilation require the selected battery-system design; illustrative circuits do not establish autonomy. The functional block is an independent explanation of this named application. Equipment-specific ratings, terminal connections and operating conditions must be established in the project documentation.

## How to read it

- Start at the named input: Battery current sensor. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Discharge-current information. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Sensor polarity determines charge versus discharge sign.
- Identify every source, protective device, isolation boundary and return. Battery capacity, DC fault duty, charging settings and ventilation require the selected battery-system design; illustrative circuits do not establish autonomy.

## Information to show or reference

- Label the source and connection reference for battery current sensor.
- Identify the destination and defined state of discharge-current information.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: Sensor polarity determines charge versus discharge sign.

## Important distinction

Sensor polarity determines charge versus discharge sign. This reference describes the named application; it does not establish a new IEC graphical symbol, an ANSI device-function number or an exact manufacturer connection diagram.

## Facts

- Representation: Functional block
- Installation focus: Substations
- Input / boundary: Battery current sensor
- Output / connection: Discharge-current information
- Lookup label: SBDM is a library lookup label, not a standard device designation.

## Public references

- [MicroGenius S2/S4 battery charger technical manual](https://www.sens-usa.com/hubfs/Controlled%20Files/Manuals/101330_MGS_User_Manual.pdf) — SENS. Public technical context for station battery and charger distribution. Battery charging modes, DC distribution interfaces and charger alarms. The application text and educational graphic are independently authored; the publisher does not certify this representation.

## Graphic scope

Independent original educational concept illustration by Elora Grid. Not a certified standards graphic or manufacturer footprint. Unitless; not to scale. Original artwork licence: https://creativecommons.org/licenses/by/4.0/. Publisher material is linked only.