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Bolt Jnr Plus Encoder Battery Replacement

FLAIR 7

The Bolt Jnr Plus (RV-13) uses internal encoder batteries to maintain axis position memory when powered off. This guide covers the warning signs, replacement procedure, and recommended replacement intervals.

Warning Signs

Flair (Classic / Flair 7) displays:

"Robot encoder battery voltage is low or has a fault"

This warning appears at startup or during a session and should not be ignored — if the battery dies completely, the rig loses all stored axis positions and must be re-zeroed.

Note: Flair 6 does NOT display this warning. If you are using Flair 6 on a Bolt Jnr+, upgrade to Flair Classic or Flair 7 to receive encoder battery alerts.

Before Replacing — Try Recharging

The encoder batteries are rechargeable. If the warning appears for the first time:

  1. Leave the rig powered on overnight (fully powered, not standby).
  2. On next startup, check if the warning has cleared.
  3. If the warning clears and stays clear: the battery was simply depleted and has recharged.
  4. If the warning persists after recharging: replace the battery.

Replacement Procedure

Battery code: MR-BAT6V1 (standard size, widely available from local electronics suppliers or Mitsubishi Electric distributors)

  1. Follow the official MRMC procedure: BoltJnrPlusEncoderBatteries.pdf — supplied with your rig as a physical or digital document. The forum (talk.mrmoco.com) closed when MRMC entered liquidation in May 2026. If you do not have the document, ask in the Flair Community WhatsApp group as other operators may have a copy.
  2. Power off the rig before beginning.
  3. Replace all batteries of the same type in the same session — do not partially replace.
  4. After replacement, re-zero all axes if position was lost (check each axis returns to its correct home position).

Replacement Intervals

Scenario Recommendation
Regular production use Replace every 2–3 years in practice
Manufacturer recommendation Yearly
Rig in storage 2–3 years Assume batteries are dead; replace before use
After replacement Replenish spares kit immediately

"Recommended replacement interval: every 2–3 years in practice (manufacturer says yearly). Robots in storage 2–3 years: batteries likely dead, encoder positions lost, re-zeroing required." — gordon_admin (MRMC)

Spares Kit

Keep at least one spare MR-BAT6V1 in the Bolt Jnr+ carry kit. After any replacement, restock immediately so the next replacement is not delayed on a job.