Watlow Series 988 - Manual (Page 115)

WATLOW Series 988 User’s Manual 7.9
Tuning, Manual Operation, Alarms and Error Codes, Chapter 7
Error Codes
[`Er3]: Ambient temperature error
The ambient temperature of the Series 988 has dropped below 32°F/0°C
or risen above 149°F/65°C. Calibration errors can also cause this error
code. Try setting
[`rSt] (Calibration Menu) to [`yES]. (Read about
Factory Calibration in Chapter 6.)
[`Er4]: RAM verification error
An internal RAM failure has occurred. Contact the factory.
[`Er5]: Non-volatile checksum error
An EEPROM checksum error was detected. Turn the power off then back
on again. If this does not clear the error, contact the factory.
[OPLP]: Open-loop detect
This error is not available while in the on/off mode. It is only active when
[OPLP] is set to [``on] (Diagnostics Menu).
[`Er9]: Configuration error
An incorrect module has been installed in the control. Contact the factory.
Error Code Actions
All of the above error codes except [`Er4], [`Er5] and [`Er9]
will result in these conditions:
• If [FAIL] is set to [bPLS] (Global Menu)…
…and the control was in automatic operation when the error
occurred, it goes into manual (% power) operation. If the output power
is less than 75% (± 5%) power and there was a change in power (< 5%)
within the last two minutes, the Series 988 switches to manual opera-
tion at the last automatic power level (bumpless transfer). If the con-
trol was in manual operation, it remains there. (Press the Auto/Man
key å once to see the error code.) The error code is shown in the
upper display for five seconds and the lower display shows the %
power. After five seconds the upper display reverts to the
[----] dis-
play.
• If the control was operating with stable output values when the error
occurred, it continues to operate at those levels on a percent-power
basis.
• If output values were not stable, or the percent output was greater
than 75%, the control outputs drop to 0% power (off).
• If [FAIL] is not set to [bPLS]…
… and the control was in automatic operation when the error
occurred, it goes into manual (% power) operation. The power level is
determined by the
[FAIL] prompt value ([`=00] to [`100] percent).