DALY BMS Explains Thin Wires for Voltage Monitoring in Large Batteries

DALY BMS, a manufacturer of battery management systems (BMS), has provided clarification on how its thin sampling wires facilitate accurate voltage monitoring for large battery packs. The company explains that the wires' thin design does not hinder reliable measurement when installed correctly.

The primary function of sampling wires is voltage acquisition, not power transmission, DALY BMS states. They operate similarly to the probes of a multimeter measuring battery terminals. A typical harness for a 20-cell battery pack includes 21 wires, where each adjacent pair measures a single cell's voltage. This is a passive measurement process requiring minimal current, typically in the microampere (μA) range.

According to DALY BMS, the high input impedance of these wires ensures that the current drawn is negligible and does not significantly affect cell capacity. Ohm's Law dictates that minimal current combined with the wires' low resistance results in only microvolt-level voltage drops, ensuring measurement accuracy.

However, the company emphasizes that incorrect installation, such as reversed or cross-connected wires, can lead to erroneous voltage readings. This can trigger false protection judgments from the BMS, like incorrect over- or under-voltage alerts. In severe cases, improper connections might expose wires to high voltages, causing overheating, melting, or damage to the BMS circuit itself. DALY BMS urges users to meticulously verify the wiring sequence before connecting the BMS.

The sufficiency of thin wires for voltage sampling thus relies on their low current demand. DALY BMS reiterates that precision in installation remains critical for ensuring overall system reliability.