Current Monitoring Relays

Current Monitoring Relays

A Few Words about 'Current Monitoring Relays'


Midland Jay Current Monitoring Relays cover almost all your requirements for monitoring of the current on your application. The original design is in our “JAP” range of established Current Monitoring relays. A few years ago we extended the range with the introduction of the “CLA2” version and then even more recently we included time to increase the coverage of applications. The CLA Current Monitoring Relays are split in to 4 versions: CLA2. Offers within the one unit Under and Over current; adjustable trip levels and LED indication. CLA1. This monitors for Under-current and incorporates an adjustable trip delay timer providing the option to ride through a short term current dip for up to 10 seconds. CLA3. Monitors for Over-current and incorporates an adjustable Trip Delay Timer providing the option to ride through a short term current surge for up to 10 seconds CLA4. This incorporates an adjustable start up delay providing the ability to ride through a Start up surge to monitor the supply to either a single phase or 3 phase AC motor for an Over-current condition. Start up time is adjustable between 1 and 10 seconds

Current Monitoring Relays


Application: Current Level relay for monitoring an AC current. 

Description: The CLA# family of supply monitoring relay is designed as a dual level current monitoring relay. It is intended for monitoring either single phase or balanced 3 phase ac loads for both under and over-current conditions.  

Alternatives: 1. For a single
Application: Current Level Relay for monitoring a DC current. 

Description:

The CLD family is a range of dual level current monitoring relays. It is intended for monitoring a dc load for both under and over-current conditions.  

Application: AC or DC Current Monitoring Relay.
 
Description:

The JAP1 family of products is designed to monitor a single phase or balanced 3 phase supply for either an under-current or an over-current condition. Features offer a choice of monitoring the current for:

•under- current on a single phase or balanced 3 phase supply 
•over-current on a single phase or balanced 3 phase supply

Please note: Only AC current monitoring is available on units which have a DC control supply.  
 
Trip Delay Timer
Where fitted the ‘Trip Delay Timer’ will inhibit the output contacts from releasing immediately a fault is detected.
The trip delay time is adjustable up to either 10 or 30 seconds depending on the model and will be either a ‘Standard’ delay or a ‘True’ delay type.
The 'Standard' delay type will require around 50% nominal supply voltage to be maintained for its operation, in the case of a total loss of power the unit
will trip with a minimal delay of approximately 0.5 seconds. This type of timer will allow the unit to ride through a short term voltage dip but not a total
power loss.
The 'True' delay timer is not dependent on the supply voltage for its operation. The timing function will be available in the case of either a partial or total
supply failure. This type of timer will allow the unit to ride through either a short term voltage dip or a total loss of power lasting up to 30 seconds.
Power On Delay Timer
Where fitted, the ‘Power On Delay Timer’ will delay the output contacts from energising immediately the supply voltage is applied to the unit for a period
of up to 30 seconds.
The supply voltage will have to satisfy the conditions set by the supply monitoring relay for a healthy supply continuously for the ‘Power On Delay’ timing
period before the output contacts will energise.
If the unit detects a fault and releases the output contacts the supply voltage will once again have to satisfy the requirements of a healthy supply continuously
for the ‘Power On Delay’ timing period before the output contacts will re-energise.