This is a rather neat universal control panel timer that fits onto a standard DIN rail mounting and accepts a control voltage of 12 to 260V. It has two buttons and an LCD display that allow the user to select from a wider range of delay and cycling functions with a huge time range that goes from 0.1 second to 999 hours.
The relay is quite unusual in that its internal relay is powered by batteries and not from the control signal. It uses a magnetic remanence style relay with two coils that can be latched in its on or off state by a short pulse. That reduces the drain on the internal lithium cells, allowing a theoretical 10 year or 1 million relay cycle life.
The relay is quite unusual in that its internal relay is powered by batteries and not from the control signal. It uses a magnetic remanence style relay with two coils that can be latched in its on or off state by a short pulse. That reduces the drain on the internal lithium cells, allowing a theoretical 10 year or 1 million relay cycle life.
My guess is the batteries are only for the display screen and setup processing, and that the batteries don't directly operate any of the mechanics.
In theory, if the relay is latching, then it could latch and the lithium cells could become unable to unlatch or flick the latch causing the thing you are trying to control with exact timing to be locked on…
I suspect the relay is a latching one.
Generally when you install one of those you use a permanent marker and black out the unused connection diagrams, leaving the one it is programmed for as the single legible one, then write the timings on the other side. Helps though that RS never removes obsolete stuff off of the manuals online, the part number will still enable you to get the manual, even if it is obsolete and you no longer have the crappy sheet of thin paper it came with.
I have been buying them. They are common parts, but with RS pricing they probably do not sell many. The true off parts though are rarer, you typically get it as a single version with true off, using a small button cell pack of Nimh cells or a supercap for some versions.