Sterling Power LR80 Pro Latch R Latching Relay - 80A - 12V / 24V

Sterling Power LR80 Pro Latch R Latching Relay - 80A - 12V / 24V

Why a latching relay over a conventional relay?

A conventional relay (such as ones used in cars to switch on your lights or control power distribution on boats etc.) These are by far the most common forms of relays produced, they are very reliable and relatively low cost yet inefficient. For instance, a standard 80A/12V relay would consume about 0.45A (staying on). So, with a 70A alternator the consumption of 0.45A for the relay is of no real importance. However, if you are planning on using a 60W solar cell on a normal ‘English’ day you would expect approximately 0.4A of current all of which shall be lost across the relay, thus, rendering the solar cell useless. So lets do the maths: with the engine off, a single conventional relay will consume in 1 day 0.45A x 24 hrs =10.8A. Per week = 75.6A.

Pro Latch R is suitable for use as one of the following:
1) Split charger ( VSR ) relay / uni + bidirectional
2) Battery protect relay ( over discharge and over charge )  
3) Engine Start Protect relay

A latching relay works in a completely differently way, instead of using power to “stay on “ it locks into position, so no matter if the circuit is ‘on’ or ‘off’ it engages a locking device (latch) which consumes no power to hold that position. On the down side they cannot be used straight out of the box like a standard relay. This is because they need a control circuit to work the internal latching device. It only needs a short burst of power to pull the contacts from one side to the other then the power must be removed, this, in itself, needs a control circuit. Sterling’s efficeincy is down to 0.0005A (0.5mA) where our competitors are at 4-12mA. So lets do the maths: with engine off our latching relay with active control circuit will consume 0.0005 x 24hrs = 0.012A per day which is 0.084A per week. Compared to a standard relay which uses 75.6A in a week a latching relay system will use nearly 1000 times less, and this is for only 1 relay, what happens if you need 2,3 or 4 on a larger installation, clearly this low power consumption latching relay is the only sensible choice if solar or wind is used to supplement the main alternator charging system.

12V or 24V is automatically selected by the product, If less than 16.5V is detected then the unit will power up as 12V, if more than 17V the unit will power up as 24V.
Fine voltage key trigger point adjustments, each function has factory preset voltage trigger points these trigger points can be customised. A magnetic swipe can be used to adjust from 10.4V- 15 V for ‘on’ voltages ( x 2 for 24V ) and 10.0V- 14.6V for ‘off’ voltages (x2 for 24V), you would perhaps customise these settings for lithium batteries.

Pre set voltage can be adjusted if required.

Specifications: