Comparison Between New & Old PMD Series Three-Phase Monitor Relays
Wednesday: May 27, 2015 : Three-Phase Monitor Relays
In May 2015, Macromatic introduced the next generation of PMD Series Three-Phase Monitor Relays. Many important features were added to the new products. These improvements along with a comparison to the previous design are summarized below:
|Current PMD Series||PMD Series|
|Mounting Configuration||35mm DIN-Rail & Panel-Mounting||35mm DIN-Rail Only|
|Dimensions||45mm W x 114mm H x 70mm L||52.5mm W x 57mm H x 89mm L|
|Line-Line Voltage Range||200-480V (PMDU)||190-500V (PMDU)|
|575V (PMD600)||480-600V (PMD575)|
|120V (PMD120)||102-138V (PMD120)|
|Line-Line Voltage Dial (PMDU)||1 Scale
Low Voltage: 190-250V
High Voltage: 380-500V
Unit auto senses the three-phase line-line voltage when applied & automatically selects the appropriate voltage
|Adjusting Line-Line Voltage Setting||Can only be made with voltage
removed–changes in setting are ignored with power applied–must remove power before a change in a setting can be recognized
|Can be made with voltage applied–any changes in settings with power applied will be immediately recognized|
|LED Fault Codes||
Printed on side of Product
Printed on top of Product for Easier Visibility (see Picture above)
|Operation with Lost Phase||
Internal logic & LED were powered from two of monitored three phases. If either of these phases is lost, unit loses power, resulting in:
No matter which of the three phases is lost, the new PMDU remains powered:
|Disable Phase Unbalance||Unbalance Knob had "Disable" setting to remove unbalance protection||Does not have "Disable" setting on Unbalance Knob–it was determined that removing Unbalance protection reduced the level of phase loss protection|
|Contact Configuration||SPDT & SPNC||DPDT|
|Increased Contact Ratings||10A @ 240VAC
No DC ratings
1/3hp @ 120/240VAC (N.O.)/
1/6hp @ 120/240VAC (N.C.)
No pilot duty
|10 A @ 277VAC/
10A @ 30VDC
1/2hp @ 120/240VAC (N.O.)/
1/3hp @ 120/240VAC (N.C.)
C300 pilot duty
To learn more about our new line of PMD Series Three-Phase Monitor Relays, please click here: ProtectMyMotor.
If you still have questions about any differences between the new & old designs, please contact Macromatic Technical Support at 800-238-7474.
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