Support FAQ

Power Supplies

A faulty power supply accounts for a significant portion of issues seen on older DynaPath controls, particularly Delta 10/20/30/40/50/60 controls. Spontaneous control re-boots and watchdog (WD) timeouts are usually traced to issues with the power supply.

The most obvious and straightforward problem to troubleshoot on a power supply is when there are no DC voltages generated by the supply. Check that the incoming AC power is within specification and that any fuses are good. If these two items check out, disconnect all loads from the power supply and then check for DC voltages to insure that there isn't a short circuit present (the control typically supplies +24VDC for any discrete inputs and outputs, as well as supplying "internal" voltages). As noted in the specifications, the power supplies used in DynaPath controls incorporate short circuit protection and should shut down if a short circuit is detected. If none of these issues exist, the power supply may simply need to be replaced.

Another common problem is a large amount of AC "ripple" on the DC voltages generated by the power supply. Excessive ripple has caused watchdog errors, loss of feedback and, in extreme cases, has caused the control to continually re-boot for no apparent reason.

DynaPath strongly recommends replacing a marginal power supply, rather than trying to repair it. A repaired power supply, while initially appearing to be in good condition, is likely to fail again within a short period. There will always be a small amount of AC ripple present on the DC voltages. An acceptable amount of ripple is less than 30 mV. Measured values higher than this indicate that the power supply should be replaced.