All of the main ranges of Albright contactors are available as single pole magnetic latching contactors. One short pulse to set (close) the contactor and another pulse of opposite supply polarity to unset (open) it again. The result is a bi-stable device that can be left in an open or closed state indefinitely with no power applied to, or consumed by the coil. As there is no coil heating these contactors can be engineered with more powerful coils and springs than with conventional contactors.
The contact ratings and all external dimensions are identical to their equivalents with conventional coils.
Contactor Operation
The operation of a single pole magnetic latching contactor requires a short duration pulse typically 0.25 seconds at the coil supply voltage to set (close) the contactor. Once set (closed) the contactor will remain set, even if there is a power outage. Subsequent pulses of the same polarity will not affect its status.
To unset (open) the contactor a pulse of 0.25 seconds duration is applied at the coil supply voltage. Once unset (open) the contactor will remain unset (open), even if there is a power outage. Subsequent pulses and voltages at the same polarity will not affect its status. To set (close) it again the polarity of the pulse must once again be reversed.
Albright offers the ML range for customers requiring an alternating coil polarity drive unit.
ML53L-60 & ML53H-96
Utilising the latest CMOS technology and surface mount design, the ML53L-60 features enhanced low voltage operation and lower power consumption together with the ability to drive all the contactor coils in the range between 12 and 60 Volts.
Contactors with coil voltages between 48V and 96V can be controlled with the new ML53H-96. These simple modules are an option to allow the operation of Albright’s range of bidirectional single pole magnetic latching contactors from a standard DC supply.
Operating Method
The ML53 is a five terminal non-sequential device. It is similar to the ML52 except that in addition to ground it has two separate inputs for set (close) and unset
(open) of the contactors. If the set (close) input is powered up it will generate a positive pulse at supply voltage of 0.25 seconds duration, long enough to set any
of our magnetic Latch contactor range. Each time this input is actuated it will generate a positive pulse. If the unset (open) input is powered up it will up generate a
negative pulse at supply voltage of 0.25 seconds duration, long enough to unset any of our magnetic latch contactor range. Each time this input is actuated it will
generate a negative pulse. Powering each input alternatively can set (close) and unset (open) the contactor
The ML53 is available in two voltage ranges; 12 to 60V, suitable for the majority of applications and 48 to 96V for applications required to energise higher voltage coils:
| Type | Voltage Range | Maximum Voltage | Minimal Nominal Voltage | Maximum Drive Current |
|---|---|---|---|---|
| ML53L-60 | 12-60V | 60V | 12V | 4A for 0.25S |
| ML53H-96 | 48-96V | 96V | 48 | 2A for 0.25S |
Dimension Drawing for ML53
Brief Specification for ML53 Series
| Description | Parameter |
|---|---|
| Initial Power-up sequence time | 10mS ±20% |
| Drive Pulse Length | 0.25S ±20% |
| ML Power Consumption | <10mA + |
| Absolute Maximum Voltage | 100V |
| Recommended Maximum switching speed | 1 operation per 10 seconds (0.1Hz) |
| Operating Temperature Parameters | -40 to +85ºC |
*Exceeding this voltage may damage the module
Limits
An ML is designed to operate one contactor coil only.
Important Note:
Magnetically Latched Contactors do not fail safe. If there is a power failure, or if the supply to the contactor coil is broken, the contactor contacts will not open
or close, i.e. they will not change state. These devices should not therefore be used in applications where the failure of contacts to open or close could result
in a hazardous situation for persons or equipment.