QUOTE (Richard Johnson @ 30 Jul 2008, 04:54) <{POST_SNAPBACK}>The big issue with changing multiple solenoids together is the abiity of the power supply - a peco PL10 for example has 4 ohm coils, so needs a momentary power of 4 amps at 16 volts.
Two will need 8 amps. THAT is why accessory decoders have problems, why you cannot use track power for solenoids and why many of you have problems with point motors.... high current needs big wire to connect things (32/02 for example) and big power supplies!
All very true... but for completness it must be pointed out that the decoders with on-board CDUs get round most of these problems. Effectively they smooth out the high current for a very short time into a low current for a longer period. Hence you only need thick wires between the decoder and the point itself, you can have thinner wires back to the power supply which can also be much lower rated (or you could use track power).
My own experience is that the MERG accessory decoder throws two SEEP solenoids in parallel and is perfectly reliable provided the SEEPs are aligned correctly (which I find a bit tricky).
Another factor influencing the number of decoders is the physical distribution of the points. If there are many close together than it probably saves space and money to drive as many as possible from a single decoder. However if a point is geographically isolated it might be better to position a single-ouput decoder nearby to avoid a long wiring run which for a solenoid would need to use some heavy gauge wire.
Two will need 8 amps. THAT is why accessory decoders have problems, why you cannot use track power for solenoids and why many of you have problems with point motors.... high current needs big wire to connect things (32/02 for example) and big power supplies!
All very true... but for completness it must be pointed out that the decoders with on-board CDUs get round most of these problems. Effectively they smooth out the high current for a very short time into a low current for a longer period. Hence you only need thick wires between the decoder and the point itself, you can have thinner wires back to the power supply which can also be much lower rated (or you could use track power).
My own experience is that the MERG accessory decoder throws two SEEP solenoids in parallel and is perfectly reliable provided the SEEPs are aligned correctly (which I find a bit tricky).
Another factor influencing the number of decoders is the physical distribution of the points. If there are many close together than it probably saves space and money to drive as many as possible from a single decoder. However if a point is geographically isolated it might be better to position a single-ouput decoder nearby to avoid a long wiring run which for a solenoid would need to use some heavy gauge wire.
