ABB Robot SMB Battery Replacement & Revolution Counter Update

By SongWei Robotics technical content team · Reviewed by an ABB service engineer · Last updated: 3 November 2026 · Applies to: ABB IRC5, RobotWare 5 / 6 / 7

Why an ABB robot loses its position after power-off

Switch off the mains to an IRC5 controller, come back later, and you may find the axis positions showing in red on the FlexPendant, with the robot refusing to run a program. The arm has not moved. What it has lost is the count of how many full turns each axis has made, the revolution counters, and without that count the controller cannot work out where the arm actually is.

That count is kept alive by a small lithium cell on the SMB, the Serial Measurement Board. While the controller has mains power the cell does very little; cut the mains and it becomes the only thing still holding the counters. Which is why it has to be replaced before it runs down. Once it is dead, every mains-off and mains-on cycle loses the counters, and the line waits while someone jogs six axes back to their reference marks.

So this guide is really about two jobs. Replacing the battery in time, a consumable swap, done with the controller still powered on, that skips the update entirely. And updating the revolution counters when you are already too late.

Two things are worth getting straight first, because both catch people out. A new battery does not bring lost counters back: if they are already gone, fitting a fresh cell changes nothing until you run the update. And strictly, the battery holds the revolution count, not the whole "position". The exact position comes from the resolver reading plus the revolution count, while the calibration values sit in the SMB and survive power-off. Put plainly, the cell is the keep-alive for the robot's zero. Replace it in time and nothing moves. Let it die and you re-teach the zero.

If 38213 or 38200 is already on your pendant, the cell is telling you it is on its way out, and you are still inside the window where a powered-on swap keeps your counters. Send us the robot type and serial number and we will confirm the correct cell for your IRB before you power anything down, remotely, no site visit.

What the battery is actually holding on to

ABB puts it precisely in the IRC5 operating manual (3HAC050941, §4.6.9): the exact position of the robot is determined using the position of the resolvers and counters that count the number of resolver revolutions, these are the revolution counters.

The same section carries the warning that explains the red text: if the positions are displayed in red, the values from the revolution counters are lost and instead the values stored on the SMB are displayed. So red is not a live position reading. It is a stored fallback value, and if the mechanical unit is uncalibrated the actual position can be very different from the number on screen.

In practice, position data is three separate things, and only one of them depends on the battery:

That split explains both the failure and the fix. Swap a healthy cell with the controller still powered and you lose nothing: the counters stay, and no calibration work is needed. Let the cell die, or power the robot down on an already-dead cell, and you lose the middle row only. Which is why the recovery is a revolution counter update and not a full recalibration: the fine calibration is still sitting in the SMB.

Which backup battery your robot takes, 2-pole or 3-pole

Here is where most orders go wrong, because there is no single part number that fits every IRB. ABB builds the SMB in two battery contact variants, and the battery has to match the variant installed in your robot.

The ABB IRB 2600 product manual (3HAC035504-001, §3.4.8) states it plainly: there are two variants of SMB units and batteries, one with 2-pole battery contact and one with 3-pole battery contact, the variant with the 3-pole battery contact has longer lifetime for the battery, it is important that the SMB unit uses the correct battery, make sure to order the correct spare parts, and do not replace the battery contact.

The pairing is fixed in ABB's own spare parts lists, and the wording is always one-way: each battery carries a note saying which SMB it can be used with, not the other way round. The 2-pole battery unit is 3HAC16831-1, and ABB's IRB 460 spare parts list notes it can only be used with SMB board 3HAC031851-001, the DSQC 633A. The 3-pole battery unit is 3HAC044075-001, and the same list notes it can only be used with SMB board 3HAC044168-001, the RMU 101.

Those board numbers shift with the robot, which is why reading one manual is not enough. The IRB 7600 spare parts list pairs the same 3HAC16831-1 with SMB unit 3HAC022286-001, the DSQC 633, and the same 3HAC044075-001 with SMB unit 3HAC046277-001, which contains board 3HAC044168-001 together with battery pack 3HAC044075-001 as one assembly. The contact variant is what stays constant across all of them. What changes is which board number the manual prints for your particular robot, so the note in your own product manual is the one to follow, not a table copied from a different model.

Both batteries need their matching cable and holder, and those part numbers differ with the contact variant too: the 2-pole battery uses cable 3HAC13151-1, the 3-pole battery uses cable 3HAC046287-001 and needs battery holder 3HAC046520-001 to fit the pack. If your robot came with an SMB replacement set rather than a bare board, the set is 3HAC046686-001, and which suffix applies depends on the robot, the battery contact variant, the SMB enclosure and the cable set, so take the suffix from your robot's service documentation rather than guessing it.

How do you tell which variant you have, without opening the base? Three ways, in order of reliability. Read the article number on the existing battery or its label. Read the SMB board identification in your IRB product manual's spare parts list. And if the base is already open, count the contact pins on the battery connector. Do not rely on the robot model alone: the same robot family shipped with both variants across production years.

What happens if you get it wrong is worth knowing before you order. A 3-pole pack will not seat into a 2-pole holder, and forcing it damages the connector. A pack that physically fits but has the wrong voltage or chemistry can leave the board running on a partly charged cell, and 38200 keeps coming back even though you changed the battery. And on some robot models the SMB battery is fed through a jumper in the robot signal cable, so unplugging that cable cuts battery power too, which can produce the same warning with a perfectly good new cell still fitted.

Two of the parts above are in our stock and can be quoted directly: the ABB IRC5 SMB backup battery 3HAC044075-001 for 3-pole contact and the ABB IRC5 SMB backup battery 3HAC16831-1 for 2-pole contact. If you are not sure which one your robot takes, send the robot serial number and the number printed on the battery, and we will confirm it before you order.

The warnings you will see on the FlexPendant

38213, Battery charge low is the one you want to catch. ABB's troubleshooting manual is blunt about it: replace the battery at a suitable opportunity, and do not turn the controller off until you have. The Chinese revision of the same document phrases the urgency differently: the battery on the serial measurement board will be depleted within no more than 2 months from the moment this message first appears. Treat that as a planning window, not a promise. Note one difference that matters at the cabinet: the "do not turn the controller off" instruction appears in the English revision and not in the Chinese one, so if your documentation is the Chinese revision, take that instruction from the English text. Caught here, the whole job is one part and a few minutes, and the counters never move.

38200, Battery backup lost means the backup is already gone, the cell is discharged or disconnected. ABB states the consequence plainly: when the SMB battery power supply is interrupted, the robot will lose the revolution counter data, and this warning will also repeatedly be logged. The manual also names two causes that are easy to miss: on some robot models the SMB battery power is supplied through a jumper in the robot signal cable, so disconnecting the cable interrupts the battery power supply, and some earlier robot versions used rechargeable batteries which must be charged for at least 18 hours before working correctly. If you have fitted a new cell and 38200 keeps repeating, check whether the cell is the rechargeable type and whether it has had its 18 hours. The way out is to fit a charged cell, then update the counters. Two rarer codes belong to the same family. 38214, Battery failure appears when a transportation shutdown of the battery failed, and ABB is precise about what that does and does not mean: the battery will still be in normal mode. Retry the shutdown, and if it keeps failing, the SMB board itself needs replacing. 38215, Battery supervision failure is a failure in the reset of the battery supervision circuit, and ABB's action is to repeat the update of the revolution counter for the joint connected to that SMB, then replace the serial measurement board if it persists.

You may also see 20032, revolution counter not updated, after the counters are lost, and 50057, joint not synchronized, at startup until the update is done. The second one tells you more than the first: ABB describes 50057 as the position of the joint after power down or failure being too far away from the position before the power down or failure. That is the mechanical consequence of losing the counters. Both point to the same recovery, covered below.

Replacing the battery without losing your zero

Safety first, because both the cabinet and the arm can bite. De-energize and lock out where your site requires it. If you power the controller down, wait for the DC-bus capacitors to discharge before touching anything inside. Released brakes can let an axis drop, so control the arm. And treat the cell like any lithium pack: no short circuit, mind the polarity, recycle the old one.

On most IRB models the SMB and its cell live in the robot base; a few configurations differ, so check your product manual if the layout looks unfamiliar. The swap itself:

1. Read the battery status on the FlexPendant and note which unit is affected.
2. Keep the controller powered on if the old cell is still alive, and that is what keeps the counters.
3. Open the SMB compartment, release the retaining clip and unplug the connector.
4. Fit the new cell. Match the contact variant first: 2-pole is 3HAC16831-1, 3-pole is 3HAC044075-001 with holder 3HAC046520-001 and cable 3HAC046287-001. Confirm it against your IRB model; send us the serial number and we will check.
5. Reconnect, clip in, and confirm the pendant shows a healthy battery status.
6. If the counters were retained, you are done, no update needed. If the cell was already dead, or an SMB or a motor has been replaced, read on.

If you would rather have a second pair of eyes before you order anything, send us the event log extract and your robot type. We will read it remotely and tell you whether the battery is really the whole story, sometimes it is not, and we would rather tell you that than sell you a cell you do not need.

Updating the revolution counters

First see what the controller itself says. On the ABB menu, tap Calibration; each mechanical unit shows one of three states:

For the update, the robot goes in Manual, motors on, enabling device held, and every axis must be jogged exactly onto its calibration reference mark, the scribe lines on each joint. Doing this away from the marks stores the wrong position. Then:

1. On the ABB menu, tap Calibration.
2. Tap the mechanical unit, then Rev. Counters.
3. Tap Update Revolution Counters.
4. Read the warning, updating may change programmed positions, and tap Yes.
5. Tick the axes to update, or Select all, then Update.
6. Confirm the second, cannot-be-undone warning with Update.
7. Wait for sampling to finish and tap OK.

Verify with a power cycle: positions should show in black, and no 50057 should appear at startup. If red text remains, an axis was off its mark, so re-jog it and repeat. Some IRB product manuals also describe the CalHall routine for a more precise update; the path above is the standard rough method, and your product manual gives the model-specific calibration positions and scales.

One boundary worth respecting, in ABB's own words: "Do not attempt to perform the fine calibration procedure without the proper training and tools." A counter update is a rough calibration. Fine calibration is a different job.

When the battery is not the problem

Red positions plus 38213 or 38200 is the battery's signature. Two alarms in the same neighbourhood are not. 38103, lost communication with the SMB, is a cabling, shielding or board problem, and the official sequence runs from connectors to shield to interference to boards. 50296, robot memory data difference, shows up when the data in robot memory is not the same as in the controller for that mechanical unit, which happens after an SMB or controller swap, a serial number mismatch, or changed system parameters: verify the configuration data, and if a board from another robot has gone in, clear its memory before transferring data from the controller. And 38216 / 38217 mean the SMB functionality check expects a newer board generation, and here the two codes are not interchangeable: 38216 means the needed functionality is available in DSQC 633C or better, 38217 means DSQC 633D or better. If you see 38216, a DSQC 633C board is enough; if you see 38217, you need 633D or better.

The battery fixes one failure family. If the log says something else, swapping a cell will not help, so send us the codes and we will tell you which family you are actually in.

Parts this guide touches, for reference. Every article number in the table links to its product page.

Making this a non-event

A cell costs next to nothing next to an unplanned stop, so most maintenance teams treat it as a calendar item: glance at the battery status screen during PM, and replace the cell on a schedule rather than on an alarm. The schedule itself is not a single number, and this is where most "replace every 12 months" advice goes wrong. ABB's own figures depend on two things: which contact variant your SMB has, and how long the robot spends powered off.

For an SMB with 3-pole battery contact, the typical lifetime of a new battery is 36 months. For an SMB with 2-pole battery contact, it is 36 months if the robot is powered off 2 days a week, or 18 months if the robot is powered off 16 hours a day. The 3-pole variant lasts longer because its standby drain is lower. The same manual also ties the alarm to a remaining-capacity threshold rather than to the calendar: 38213 appears when the remaining backup capacity with the robot powered off is less than 2 months, and the IRC5 operating manual puts the electrical trigger at less than 3 Ah left in the cell.

So the practical rule for your own fleet is not "every 12 months". It is: check the contact variant, work out how long your robots sit powered off in a normal week, and take the interval from your IRB product manual, which is the figure ABB ties to your specific model.

There is also an official routine for one specific situation. If a robot is being shipped or stored for months, SMB units with a 2-pole battery contact have the Bat_shutdown service routine, which switches the battery backup off to save the cell. On 3-pole units ABB says this function shall not be used, since the power consumption is so low that it is not needed. Two things to know before you run it: jog the robot to its calibration position first, and expect the counters to be gone at the next power-up. The backup switches itself back on automatically, but the counters do not come back with it, so you update them once and the calibration values are still there.

The manual gives the current numbers for that routine, which is useful when you are sizing a storage period: the consumption in ordinary shutdowns is approximately 1 mA, and in sleep mode it drops to 0.3 mA.

FAQ

What happens if the SMB battery dies?

The revolution counters are lost the next time mains power goes off. Positions show in red, the robot refuses to start a program, and you update the counters before production resumes. The calibration values are not lost, so it is an update, not a recalibration.

Does a dead battery mean I lose the robot's calibration?

No. The fine calibration lives in the SMB serial memory and survives power-off. What dies with the cell is the revolution count, which is why a counter update, not a full calibration, puts you back.

How often should the battery be replaced?

It depends on the contact variant and on how long the robot sits powered off. ABB gives 36 months for a new battery on an SMB with 3-pole contact; on 2-pole contact it is 36 months if the robot is powered off 2 days a week, or 18 months if it is powered off 16 hours a day. Replace on that schedule or as soon as a low-charge warning appears, and take the interval for your model from your IRB product manual.

Which battery does my robot take, 2-pole or 3-pole?

Check the article number printed on the existing battery, or the SMB identification in your IRB product manual's spare parts list. The 2-pole contact takes 3HAC16831-1; the 3-pole contact takes 3HAC044075-001 with holder 3HAC046520-001. The board it pairs with depends on your robot, so take the pairing from your own manual's note. They are not interchangeable, and ABB explicitly warns against replacing the battery contact to make a mismatched pack fit.

Can the battery be replaced while the robot is in production?

Plan it into a normal stop, with the controller still powered on, and the powered-on part is what keeps the counters. Done that way, the job takes minutes and production is not affected.

What is alarm 20032?

"Revolution counter not updated", the controller's reminder that the counters were lost and have not been updated yet. Move the axes to the sync position and run the update, and it clears.

Why do the axis positions show in red?

Red text means the stored counter value is gone and the pendant is showing the SMB fallback value instead. Until you update the counters, the robot will not run a program.

The robot was stored or shipped for months, why do the counters need updating now?

If Bat_shutdown was run on a 2-pole SMB to save the cell during transport, the counters were switched off with it. The backup re-enables itself at power-up, but the counters do not come back, so one update and you are done, calibration values intact.

What is the difference between 38213 and 38200?

38213 is the early warning, the cell is running low, replace it, and do not power down first. 38200 means the backup is already lost: the counters are at risk or gone, and you will need the update after fitting a charged cell.

I fitted a new battery and 38200 keeps coming back, what should I check?

Four things in this order. Whether the battery is the rechargeable type, which ABB states must be charged for at least 18 hours before working correctly. Whether the robot's SMB battery is fed through a jumper in the robot signal cable, so unplugging that cable also cuts battery power. Whether the new pack matches the contact variant. And whether the cell itself is charged, because a fresh pack sitting in a depleted state produces exactly the same warning.

What information do you need to quote a battery?

Robot type and serial number are enough to start. The article number on the battery or its contact variant helps us confirm faster, and the event log code tells us which step you are at, but send the serial number first if that is all you have.

Can I ask a technical question without buying anything?

Yes, and that is usually the right first step. Send the code and your robot type and we will help you read it remotely. If the root cause is not the battery, we will tell you so rather than sell you a cell you do not need.

If you need a hand

Three situations, one route. If you have an alarm on screen, 38213, 38200, red positions, send the code plus your robot type and serial number, and we will confirm the right cell and quote it. If you are not sure the battery is the problem, send the event log and we will read it before you order anything. And if you are planning ahead, tell us your IRB models and your next planned stop, and we will help you line the cells up so the swap happens powered on. All of it remote, your engineers stay on site, we work alongside them.

Sources

• ABB, Operating manual - IRC5 with FlexPendant, 3HAC050941-001 Rev G: §4.6.9 (positions and revolution counters, red-text fallback), §5.9.2 (Bat_shutdown, 1 mA / 0.3 mA, 3 Ah alert threshold), §10.1 to 10.2 (calibration status, updating revolution counters).
• ABB, Operating manual - Troubleshooting IRC5, 3HAC020738-001 Rev AA: event log 38200 / 38213 / 38214 / 38215 (p. 192 to 193), 20032, 38103, 38216 / 38217, 50057, 50296.
• ABB, 故障排除手册（报警代码）, 3HAC020738-010 Rev L: Chinese revision of the same document, 38213 wording with the two-month window.
• ABB, Product manual - IRB 2600, 3HAC035504-001 Rev G: §3.4.8 (2-pole and 3-pole battery contact variants, battery lifetime by downtime, 38213 remaining-capacity threshold).
• ABB, Product manual - spare parts IRB 2600, 3HAC049106-001 Rev S: battery unit 3HAC16831-1 and 3HAC044075-001 with their compatible SMB boards.
• ABB, Product manual - spare parts IRB 460, 3HAC040628-001 Rev Q: the same battery and contact pairings, battery cable and battery holder article numbers.
• Your IRB product manual: model-specific calibration positions, scales and battery interval.

Independent technical content, not an official ABB document. ABB, IRC5, FlexPendant, IRB and RobotWare are trademarks of ABB. Follow your product manual and your site's safety rules: de-energize, lock out, wait for the DC bus to discharge, qualified personnel only.

Last reviewed 3 November 2026, verified against 3HAC050941-001 Rev G and 3HAC020738-001 Rev AA. To re-check this yourself, open the event log on your pendant and compare the wording of 38213 and 38200 against the manual revision your controller documentation set uses.