Midmark M9® -05x / M11® -05x Sterilizer Heater Relay Board Test and Repair

WARNING

To prevent risk of shock always disconnect power before removing covers or performing any service procedure.

WARNING

Some procedures require power to be connected with covers removed. Line voltage is present. Use extreme caution to prevent electric shock.

 

Model

 M9 -050, -053 M11 -050, -051, -053
Serial Number All All

M9/M11 Steam Sterilizer Heater Relay Testing

For proper test point readings, meter leads need to penetrate PC board conformal coating.

 

1.Set meter to VDC.

2.Place meter probes on desired points and check reading.
—Signal to energize relay (Top of R8 and TP292) *Heating Element On*

The click of the relay energizing should be audible.

 

Meter Reading

Required Action

VDC Signal to energize relay (Top of R8 and TP292) *Heating Element ON* = approximately 3.3 VDC

PC board is OK.

VDC Signal to energize relay (Top of R8 and TP292) *Heating Element OFF* = approximately 0 VDC

PC board is OK.

Any other reading

Replace PC board.

M9/M11 Steam Sterilizer Heater Relay Testing

For proper test point readings, meter leads need to penetrate PC board conformal coating.

For proper voltage readings, the circuit must be connected (loaded) to the component—such as a solenoid valve you are checking.

1.Set meter to VAC.

2.Place meter probes on desired points and check reading.
• VAC to relay board (J2 one of the 6 pins shown and TP273)
• VAC out of relay (TP6 and TP273) *Heating Element On*

The click of the relay energizing should be audible.

 

Meter Reading

Required Action

VAC to relay board (J2 one of the 6 pins shown and TP273) = approximately 115 VAC / 230 VAC

PC board is OK.

Any other reading

Replace PC board.
VAC out of relay (TP6 and TP273) *Heating Element ON* = approximately 115 VAC / 230 VAC

Relay board is OK.

VAC out of relay (TP6 and TP273) *Heating Element OFF* = approximately 0 VAC

Relay board is OK.

Any other reading

Replace relay board.