Precor Error Code 10 Line Frequency Out of Acceptable Range

Feb 17, 2022

Applies to Treadmills mfg. dates 2006 and later

Issue Symptoms

The AC line frequency must be either 50Hz or 60Hz for Experience™ Series treadmills built 2006-2013, and between 45Hz and 65Hz for units built 2014 and later. Error 10 is triggered if the line frequency moves outside the acceptable range, or if electrical noise is generated, causing a perceived change in frequency.

Error 10 can also be caused by electrical wiring and supply issues, such as shared neutrals or AC hot and AC neutral wires being reversed. If facility power is lost and a backup generator switches on, the frequency can be off for a short time, causing Error 10.

Troubleshooting steps

Verify electrical supply

1. Verify electrical supply. Treadmills must be installed on an AC 20-amp dedicated branch circuit. If another piece of equipment is sharing a circuit with the treadmill, it can create enough electrical noise to make AC line frequency identification impossible.
2. Most line frequency detection systems monitor the AC line frequency on the hot AC line. On a reversed 120 VAC(Voltage in an alternating current circuit) circuit, the monitoring takes place on the neutral (ground) side of the AC line. Many of the monitoring systems are incapable of detecting line frequency on the neutral wire. It must first be determined if the reversal is in the AC wiring feeding the treadmill or in the treadmill internal wiring. The hot and neutral wires can be verified by measuring each in reference to AC (green wire) ground.
3. Though unlikely, the AC line frequency could be out of limits. This is more likely to occur in countries where AC power systems may not be well controlled. There is little that can be done in this case.
4. If a generator is used during a power outage, during the time the generator is coming up to speed, the line frequency may be detected as incorrect.
5. Sometimes AC being fed into the distribution system is too electrically noisy to allow correct line frequency identification. This can be caused by other equipment within the AC distribution system creating the electrical noise. Identifying the source of the electrical noise can be difficult. There is little that can be done in this case.