THREE PHASE MONITOR RELAYS

Three-Phase Monitor Relays continuously monitor and detect voltage faults to protect equipment in three-phase systems. These relays retain indication and continue monitoring even with a lost phase. True RMS voltage measurement ensures more accurate sensing across more applications.

Protect Equipment Against Premature Equipment Failure

Three-Phase Monitor Relays are available with plug-in or Din-rail enclosures that offer protection from a combination of voltage faults: Phase Loss, Phase Reversal, Phase Unbalance, Under Voltage, or Over Voltage. These relays are compatible with most Wye or Delta systems with no connection to neutral required. Take a quick look at these popular products from Macromatic, PMPU in the PMP Series, and PMDU in the PMD Series. 

PLUG-IN

PAP, PCP, PLP and PMP Series with plug-in enclosures use standard 8 pin octal sockets. These relays have a wide universal voltage range for use in more global applications.

DIN-RAIL

PBDU Series (17.5 mm wide) and PMD Series (52.5 mm wide) mount on 35 mm DIN-rail. Both can be panel mounted with two screws by extending the black clips from under the relays. Full fault indication on top of units facilitates easy troubleshooting.

PC1 WITH COMMUNICATION - DIN-RAIL

PBDU Series (17.5 mm wide) and PMD Series (52.5 mm wide) mount on 35 mm DIN-rail. Both can be panel mounted with two screws by extending the black clips from under the relays. Full fault indication on top of units facilitates easy troubleshooting.

Communication Platform
TF_Communication_Platform
  • None (23)
  • Modbus TCP (1)
Enclosure Style
TF_Enclosure_Style
  • None (16)
  • Additional SPNO Contact for Signaling Secondary System (3)
  • Fixed Trip Points & Time Delays (w/ Adjustable Monitored Voltage) (3)
  • Adjustable Trip Points & Time Delays (1)
  • Local Adjustment (PC1MDUL) (1)
Protection
TF_Protection
  • PHASE LOSS, PHASE REVERSAL, PHASE UNBALANCE, UNDERVOLTAGE & OVERVOLTAGE (10)
  • Phase Loss, Phase Reversal & Undervoltage (5)
  • Phase Loss, Phase Reversal, Voltage Unbalance, Undervoltage & Overvoltage (3)
  • PHASE LOSS & PHASE REVERSAL (2)
  • PHASE REVERSAL (2)
  • PHASE LOSS, PHASE REVERSAL & UNDERVOLTAGE (ALL TRIP), UNBALANCE (INDICATION ONLY-NO TRIP) (1)
  • Phase Loss, Phase Reversal & Voltage Unbalance (1)
Output
TF_Output
  • 10A SPDT (13)
  • 10A DPDT (3)
  • 5A SPDT + 5A SPNO (3)
  • 5A SPDT (2)
  • 5A SPDT/SPNO (2)
  • 5A DPDT (1)
Monitored Voltage
TF_Monitored_Voltage
  • 190-500V AC (9)
  • 460-600V AC (6)
  • 102-138V AC (3)
  • 190 - 600V AC (1)
  • 208 - 480V AC (1)
  • 208VAC (1)
  • 240VAC (1)
  • 400VAC (1)
  • 480VAC (1)
Standard Modifications
TF_Standard_modification
  • None (16)
  • Additional SPNO Contact for Signaling Secondary System (3)
  • Fixed Trip Points & Time Delays (w/ Adjustable Monitored Voltage) (3)
  • Adjustable Trip Points & Time Delays (1)
  • Local Adjustment (PC1MDUL) (1)

Need a custom engineered product? We offer engineering assistance and quick turnarounds on prototypes.

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PLP Series

Communication Platform:

None

Monitored Voltage:

460-600V AC

Output:

10A SPDT

Protection:

PHASE LOSS & PHASE REVERSAL

Standard Modifications:

None

Enclosure Style:

None

$92.68

PLP Series

Communication Platform:

None

Monitored Voltage:

190-500V AC

Output:

10A SPDT

Protection:

PHASE LOSS & PHASE REVERSAL

Standard Modifications:

None

Enclosure Style:

None

$79.75

PMD Series

Communication Platform:

None

Monitored Voltage:

102-138V AC

Output:

10A DPDT

Protection:

PHASE LOSS, PHASE REVERSAL, PHASE UNBALANCE, UNDERVOLTAGE & OVERVOLTAGE

Standard Modifications:

None

Enclosure Style:

None

$177.12

PMD Series

Communication Platform:

None

Monitored Voltage:

460-600V AC

Output:

10A DPDT

Protection:

PHASE LOSS, PHASE REVERSAL, PHASE UNBALANCE, UNDERVOLTAGE & OVERVOLTAGE

Standard Modifications:

None

Enclosure Style:

None

$191.72

PMD Series

Communication Platform:

None

Monitored Voltage:

190-500V AC

Output:

10A DPDT

Protection:

PHASE LOSS, PHASE REVERSAL, PHASE UNBALANCE, UNDERVOLTAGE & OVERVOLTAGE

Standard Modifications:

None

Enclosure Style:

None

$184.42

PMP Series

Communication Platform:

None

Monitored Voltage:

102-138V AC

Output:

10A SPDT

Protection:

PHASE LOSS, PHASE REVERSAL, PHASE UNBALANCE, UNDERVOLTAGE & OVERVOLTAGE

Standard Modifications:

None

Enclosure Style:

None

$131.93

PAP Series

Communication Platform:

None

Monitored Voltage:

208VAC

Output:

10A SPDT

Protection:

Phase Loss, Phase Reversal & Undervoltage

Standard Modifications:

None

Enclosure Style:

None

$86.21

PMP Series

Communication Platform:

None

Monitored Voltage:

460-600V AC

Output:

10A SPDT

Protection:

PHASE LOSS, PHASE REVERSAL, PHASE UNBALANCE, UNDERVOLTAGE & OVERVOLTAGE

Standard Modifications:

None

Enclosure Style:

None

$152.99

PAP Series

Communication Platform:

None

Monitored Voltage:

240VAC

Output:

10A SPDT

Protection:

Phase Loss, Phase Reversal & Undervoltage

Standard Modifications:

None

Enclosure Style:

None

$86.21

PMP Series

Communication Platform:

None

Monitored Voltage:

190-500V AC

Output:

10A SPDT

Protection:

PHASE LOSS, PHASE REVERSAL, PHASE UNBALANCE, UNDERVOLTAGE & OVERVOLTAGE

Standard Modifications:

Adjustable Trip Points & Time Delays

Enclosure Style:

Adjustable Trip Points & Time Delays

$140.37

PAP Series

Communication Platform:

None

Monitored Voltage:

400VAC

Output:

10A SPDT

Protection:

Phase Loss, Phase Reversal & Undervoltage

Standard Modifications:

None

Enclosure Style:

None

$92.68

PMP-FA8 Series

Communication Platform:

None

Monitored Voltage:

190-500V AC

Output:

10A SPDT

Protection:

PHASE LOSS, PHASE REVERSAL, PHASE UNBALANCE, UNDERVOLTAGE & OVERVOLTAGE

Standard Modifications:

Fixed Trip Points & Time Delays (w/ Adjustable Monitored Voltage)

Enclosure Style:

Fixed Trip Points & Time Delays (w/ Adjustable Monitored Voltage)

$117.91

Frequently Asked Questions About Three-Phase Monitor Relays

 
 
 

Three-Phase Monitor Relay Downloads

Three-Phase Monitor Relay Competitive Comparison

Three-Phase Monitor Relay Brochure

PC Series Three-Phase Monitor Relays With Communication Brochure

Knowledge Base Articles

Technical reports to answer your questions

Knowledge Base Articles

Rapid Cycling of Control Switch Damages Large Pumps or Compressor Motors

Issue: How do I prevent a Bouncing Control Switch Due to Splashing Water from Rapidly Energizing One Load and Then the Other?   Solution/Resolution:  In Figure A, a single Control Switch could be susceptible to splashing water which would cause rapid opening & closing of the Control Switch.  Each time this happens, one Load is rapidly […]

Knowledge Base Articles

Interactive Competitive Cross-Reference

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Knowledge Base Articles

Troubleshooting for a Phase Reversal (Phase Sequence) Problem

Issue: I have purchased one of your three phase monitor relays and have connected it per the diagram on the unit. However, I cannot get the unit to operate–it just won’t turn on. What’s wrong? Solution/Resolution: Most problems when first installing and applying a three-phase monitor relay are due to phase sequence issues. Although you […]

Knowledge Base Articles

Troubleshooting for a Phase Reversal (Phase Sequence) Problem

Issue: I have purchased one of your three phase monitor relays and have connected it per the diagram on the unit. However, I cannot get the unit to operate–it just won’t turn on. What’s wrong? Solution/Resolution: Most problems when first installing and applying a three-phase monitor relay are due to phase sequence issues. Although you […]

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