NCE QSnap-Mk2 User manual

QSnap-Mk2
Version 1.0
FOR TWIN COIL SWITCH MACHINES ONLY
$69.95
All new easy programming!
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‚Control for 4 twin coil solenoid type switch machines (Atlas, Peco, etc)
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‚Supports the full range of DCC accessory addresses (1-2044)
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‚Runs from track power or external 9-15 Volt DC power supply
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‚Easy address programming, no need to connect it to programming track
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‚Inputs for local control panel push buttons
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‚Simple hook up, 2 wires to the track, 2 wires to each switch machine
Age
14+
Warning: This product contains chemicals known to the state of California to cause
cancer, birth defects or other reproductive harm.
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Notes:
This decoder is designed to control twin coil (dual solenoid) type switch machines.
There are four mounting holes at the corners of the QSnap.
Wiring:
See the diagram below for wiring particulars. The only required wires are two wires to
the track and two wires to each machine. It is OK to use the QSnap for control of less
than 4 machines.
Last revised: 7 October 2014 Copyright 2014 NCE Corp Page2
QSnap wiring diagram
To Track
PROGRAM
OUTPUT
ADDRESS
DISPLAY
OUTPUT
LEDS
External DC
Power
(optional)
Power
Select
Switch
DCC
DC
SELECT OUTPUT
Twin Coil
Switch
Machine
Twin Coil
Switch
Machine
Twin Coil
Switch
Machine
Twin Coil
Switch
Machine
Common
Common
Common
Common

If you have never used a QSnap before:
We recommend trying the decoder out first before installing it on the layout.
Connect a twin coil switch machine to screw terminals 1A/1B of the decoder with the
common (center) connection of the switch machine to ‘+’.
Connect two wires from the decoder track connection to your DCC system.
Make sure the small switch next to the track connection is moved to the ‘DCC’ position.
When you first apply power to the QSnap the address display will show some numbers
(the software version) then 3 horizontal bars for about 1 second followed by vertical
bars”wig wagging” back and forth on the display. The wig-wagging indicates the
decoder is receiving DCC information and is ready for use.
Press the ‘SELECT OUTPUT’ button the decoder until the output 1A/1B LED lights
(each push of the button will select a different output - on the ninth push all LEDs will
turn off). The address display will now start indicating the output currently programmed
for that output. For a factory fresh QSnap output #1 it will flash 1. If you select output 2
it will flash 2 and so on as indicated below:
Factory default values for decoder
Output 1 factory programmed to accessory address 1
Output 2 factory programmed to accessory address 2
Output 3 factory programmed to accessory address 3
Output 4 factory programmed to accessory address 4
Now let’s actually test the decoder output #1.
Use your DCC system to throw the switch. The instructions below can be used for
throwing a switch depending on which DCC system you have:
To throw a switch using the NCE system:
Press ‘SEL ACCY’
Type in the desired accessory number followed by ‘ENTER’
Push ‘1’ (or ‘2’) to throw the switch.
To throw a switch using a Digitrax system:
Press ‘SWCH’
Type in the desired accessory number
Push ‘OPTN’ to throw the switch.
To throw a switch using a Lenz system:
Press ‘F’
Press ‘5’
Type in the desired accessory number followed by ‘ENTER’
Push ‘+’ (or ‘-’)
If throwing the switch one way doesn’t do anything, try the other direction. You should
be rewarded with the Tortoise reversing its position.
Last revised: 7 October 2014 Copyright 2014 NCE Corp Page3

Address programming:
The Qsnap cannot be programmed on your programming track. It is always
programmed while connected to the mainline track. This decoder can be programmed
by all systems that support accessory control using the procedure below.
To program an output to a new address using any DCC system:
1) Connect wires from the track to the decoder DCC terminals.
2) Make sure the Power Select Switch is set to DCC.
3) Push the SELECT OUTPUT button until the LED corresponding to the output
lights.
4) Push the PROGRAM OUTPUT button (notice the display flashes “P" now) When
the display is flashing you have one minute to complete the next step or the
decoder will exit programming mode.
5) Use your DCC system to select and operate the switch (see above).
6) The decoder will accept that switch address as its new address and begin
showing its new address on the address display. It will show the address one
digit at a time in sequence.
You may confirm the address for any output at any time by pressing the OUTPUT
SELECT button until the appropriate output LED lights. The address for that output will
be displayed.
Setting other options in the QSnap:
Use Accessory OPs mode programming (“PROG” followed by “7” on NCE systems).
If you have an entry level system that does not support Accessory OPs mode
programming follow the instructions on the back page for setting CVs with Loco Ops.
For CV561 through CV568 use the accessory address for the corresponding output
number. For all other CVs use the accessory address programmed for output 1.
Reversing the polarity of an output:
Each of the outputs can have its polarity reversed by programming a CV for that output
For output #1 program CV561 to a value of 0 (default) for normal polarity, 1 for reverse.
For output #2 program CV562 to a value of 0 (default) for normal polarity, 1 for reverse.
For output #3 program CV563 to a value of 0 (default) for normal polarity, 1 for reverse.
For output #4 program CV564 to a value of 0 (default) for normal polarity, 1 for reverse.
If your DCC system does not support OPs mode programming for accessories you can
just swap the two wires to the switch machine.
Note:CV548 should be programmed via Accessory Ops mode programming to the
address of output 1 only.
Setting outputs to toggle when used with optional push buttons
Setting CV548 to 1 will cause pushbuttons “toggle” the switch machine output. Each
press of a button will alternate the switch position. Setting CV548 = 1 enables the
toggle option. CV548 = 0 disables it.
CV548 is “global” to the Switch8-Mk2, meaning it will affect all button commands
coming from the Button Board. (Factory default = 0)
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Pushbutton Lockout (CV556):
On some layouts it may be desirable to disable operation of the local control
pushbuttons. Setting CV556 to a value of 1 prevents operation of all the decoder
outputs by the optional Button Board pushbuttons. Setting CV556 to 0 enables
operation of these buttons. You can disable or enable ALL decoders on the layout at
the same time by using the accessory decoder broadcast address of 2044 when
programming CV556. CV556 is “global” to the Switch8-Mk2, meaning it will lockout all
button inputs from the button board. (Factory default = 0)
Notes on CV556:
CV556 should be programmed via Accessory Ops mode programming to the address of
output 1 only.
CV556 is not ‘sticky’. The decoder will not rmember that CV556 was programmed the
next time the layout is powered up.
Output On Time:
The ‘On Time’ or time that the output is active can be controlled for each output
individually. Occasionally you will an especially free throwing switch machine that will
travel all the way to the mechanical stop on the machine then bounce back away from
the stop. This means that the decoder is throwing the machine with too much energy.
By controlling the time that the output is activated we can control how much energy is
transferred from the decoder to the switch machine. The factory default value for this is
100mS which is usually satisfactory. If you find you need more or less energy you can
program the decoder (in increments of 4mS or 4/1000s of a second). CV577 through
CV580 are used to control the time. A value of 25 = 100mS (default) higher or lower
values may be programmed. Programming the CV=0 will cause the output to remain
on until the turnout is thrown to the opposite position.
CV577 - On time for output 1 (100mS = value of 25 default)
CV578 - On time for output 2 (100mS = value of 25 default)
CV579 - On time for output 3 (100mS = value of 25 default)
CV580 - On time for output 4 (100mS = value of 25 default)
Factory reset:
To reset the QSnap to original factory setting program CV8 to 8. A reset will only be
performed if you program CV8=8 via Accessory OPs mode programming to the
address of output 1.
Upon reset all settings will revert to the factory default setting as indicated below.
Factory default values for decoder
The Switch8-MK2 is factory programmed to the following values
Output 1 = accessory address 1
Output 2 = accessory address 2
Output 3 = accessory address 3
Output 4 = accessory address 4
CV548 is set to 0 (normal dual pushbutton operation by the optional Button Board)
CV556 is set to 0 (pushbutton lockout not engaged)
CV561 is set to 0 (normal output polarity)
CV562 is set to 0 (normal output polarity)
CV563 is set to 0 (normal output polarity)
CV564 is set to 0 (normal output polarity)
CV577 is set to 25 (100mS on time)
CV578 is set to 25 (100mS on time)
CV579 is set to 25 (100mS on time)
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CV580 is set to 25 (100mS on time)
DC power option
A DC power connector is provided if you wish to use external power to run the decoder
and switch machines. his will enable the Switch8-Mk2 will ride through DCC track
shorts without power interruptions. Use a power supply providing between 9 and
15VDC with a 2.5/5.5mm plug, center positive (The NCE P114 is a good option here).
The power supply should be able to supply at least 200mA. If you connect an external
supply move the DC/DCC Power Select Switch to the DC position.
The DC voltage for the switch machines will be approximately 2 volts less than twice the
DC volts. Example : 12Vdc will yield about ((2 x 12) - 2) or 22 volts to the switch
machine.
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Other technical stuff:
vWe have successfully controlled two Atlas switch machines with one decoder output
when used in a crossover. We can't guarantee this will work in all cases.
v
Indications shown on Address Display
Decoder has
power but is
not receiving
DCC information
"Wig-Wag"
receiving
DCC info and
is operational
Flashing "P"
decoder is
ready to accept
new address
Programming CVs with systems that don’t support Accessory OPs mode
programming:
Press the SELECT OUTPUT button on the QSnap until the button for output #1 lights.
Press PROGRAM OUTPUT (the display should start flashing ‘P’)
Use loco OPs mode programming (Program on the Main) to program the desired CV.
Any loco address can be used for this.
Repeat the steps above for each CV you wish to program.
If the programming “takes” the display will stop flashing.
Note:
The display will only flash for about 1 minute. When it stops flashing the QSnap will not
accept programming. If it times out and stop flashing before you finish programming just
press PROGRAM OUTPUT again.
Note:
You can only program CVs using Loco OPs mode when output #1 is selected. If any other
output is selected Loco OPs will not work (only Accessory OPs works with all outputs)
Optional push buttons:
Normally open momentary push buttons or toggle switches will work with the QSnap.
Grounding terminal 1N of the button board will activate output 1 of the QSnap to the
“normal” position. Grounding 1R will throw the Switch8 to the “reverse” position. The
other terminals on the QSnap work similarly to activate the corresponding outputs.
Last revised: 7 October 2014 Copyright 2014 NCE Corp Page7

NOTES:
The warranty is voided if the decoder is miswired, electrically modified or connected to more than 22 volts.
Warranty
This decoder is fully factory tested and warranted against manufacturing defects for a period of 1 year. As the
circumstances under which this decoder is installed can not be controlled, failure of the decoder due to
installation problems can not be warranted. This includes misuse, miswiring, operation under loads beyond the
design range of the decoder or short circuits. If the decoder fails for non-warranted reasons NCE will replace
the decoder, no questions asked, for $20 US plus $2 shipping. For warranty or non-warranty replacement send
the decoder (an any payment, if required) to:
NCE Warranty Center, 82 East Main Street, Webster, New York 14580
The terms Power Pro, ProCab, Power Cab, the NCE logo with “Power of DCC” slogan and the distinctive shape of the
ProCab with thumbwheel and LCD are trademarks of NCE Corporation. Digitrax is a trademark of Digitrax Inc.
Last revised: 7 October 2014 Copyright 2014 NCE Corp Page8
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