Schleicher SNO 2012 User manual

Safety Switching Devices
Emergency-Stop Relay
PI 0067-0703 E SNO 2012
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Basic unit for Emergency-Stop and
Safety Gate Applications
•Basic unit accordingtoDIN EN 60204-1 and EN 954-1
•EN 954 category 4
•Stop category 0 acc. EN 60204-1
•WithcrossmonitoringandRESETkeymonitoringandsimultaneitycheck
•Single or dual channel input control circuit for contacts or semiconduc-
tors
•6NOsafetycontacts,4NCcontrolcontactspositivelydriven
•OSSDcompatible
Front View
SUPPLY LED green
CH1 LED green
CH2 LED green
K1 LED green
K2 LED green
K3 LED green
1gg
Device and Function Description
The Device is a dual-channel safety switching device for emergency stop equipment conforming to EN 60204-1, with self-monitoring on each ON-OFF cycle and
positively driven relays. After the supply voltage is applied to terminals A1/A2, and if the E-Stop momentary contact switch is not activated, the control logic is
energized with the RESET switch (LED K3 is illuminated). This triggers the internal relays K1 and K2. The latter becomes self locking through their own con-
tacts. After this switch-on phase, the six enabling current paths, which are intended for the output, are closed (terminal connections 13 to 63 / 14 to 64) and the
four control contacts are opened (terminal connections 71 to 01 / 72 to 02). Five LEDs provide a display, and these LEDs are associated with the safety chan-
nels CH1, CH2 and the supply voltage. If the E-Stop switch is activated, the current leads for the K1 and K2 relays are interrupted. The enabling current paths
at the output are opened and the control contacts are closed. The control contacts 71/72 and 81/82 are related to the internal relay K1, 91/92 and 01/02 to the
internal relay K2. This feature allows an additional diagnosis of the internal status of the device by using external devices conected to these terminals. With a
two-channel connection of the E-Stop switch and cross monitoring wiring of the E-Stop circuit, it is possible to monitor the presence of a short circuit between
the connected cables (cross monitoring) and ground faults. An internal electronic circuit protects the emergency-stop relay from damages. After eliminating the
fault the item will return into operation after about 3 s.
RESET key monitoring
The SNO 2012-xx is equipped with (or without) the monitoring feature for the RESET key. For the specific use in the emergency-stop applications with moni-
toring of the the RESET key, the latter must be connected to terminals S12/S34 and terminals Y1/S37 have to be jumpered. For those applications with protec-
tive gates a manual RESET (terminals S12/S34 ) or an automatic RESET can be performed according to the requirements of the safety function. Where an
automatic RESET must be performed, it is necessary to connect terminals S12 and S34 and let terminals Y1 and S37 unjumpered. In case of RESET key
monitoring, the device can be enabled with the falling edge of the signal at the RESET key (RESET released). This only allows a manual START of the device.
An automatic START is with these connections not possible (see also function diagram). If the RESET key is not monitored the device can be used for those
dynamic applications (such as protective gates) where an automatic START is necessary. In this case the device can be enabled with the rising edge of the
signal (closing the RESET key): connections S12 to S34 and Y1/S37 open terminals.
Simultaneity check
The use of safety limit switches for single or dual channel circuit in the protective gate application depends from the required safety level. The SNO 2012-xx
features a dual channel control and asimultaneity checkofthe limit switches on request.Preconditionfor a simultaneity check ts ≈ 0,5s isthepositionofthelimitswitches.
Thelimitswitchesmustbepositionedso that channel 1 (terminals S11/S12) has toclosebeforechannel2(termi nals S21/S22) does. If channel 2 closes before channel 1
the simultaneity check is switched off (ts= ∞ ).
Correct use of the system
The SNO 2012 is a safety switching device. It is used as a base unit for monitoring control units such as emergency stop buttons and position switches. Emer-
gency stop devices and guards are part of safety-related equipment on machines to protect from injuries and damage to materials and machines.
Notes
• The input circuit allows connecting of sensors with self testing semiconductor outputs (e.g. light barriers with OSSD).
•The safety category according to EN 954-1 also depends from the external circuit, the choice of the transducer_ and is location on the machine.
•Insulation on external wiring should not be cut back more than 8 mm.
• To multiply the enabling current paths, the expansion units or external contactive elements with positively driven contacts can be used.
•External fuse protection for the device and the contacts should not exceed 6 A type gG.
Please observe instructions from safety authorities.

Safety Switching Devices
Emergency-Stop Relay
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Function Diagrams Emergency-Stop Application
(Installation 2) Safety Gate Application (Installation 3)
A1/A2 Supply voltage LED SUPPLY
S11/S12 E-Stop / Safety gate contact S1 (LED CH1)
S21/S22 E-Stop / Safety gate contact S2 (LED CH2)
S12/S34 Reset
LED K3
Y1/S37
Y1/Y2
LED K1
LED K2
13/14, 23/24, 33/34, 43/44, 53/54, 63/64
71/72, 81/82
91/92, 01/02
tMMin. switch-on time, tA1/2 Response time, tRRelease time at E-Stop,
tSSimultaneity check, tWRecovery time
Connection Diagram
K1
CH1(+)
SUPPLYFEEDBACK
CONTROL-LOGIC
_
CH2(+)(-) K2
RESET
K3
KS0375-1
Only AC devices are fitted with PE terminal.

Safety Switching Devices
Emergency-Stop Relay
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Installation Install the Emergency Stop Relay according to the terminal
connection diagram. Follow the wiring diagrams.
1Single Channel
Emergency Stop with
manual START
3Protective gate, two channel
with automatic START
1.1 Jumper 3a Limit switch S1
1.2 Feedback circuit
(external contactors*) 3b Limit switch S2
1.3 RESET 3.1 Feedback circuit (ex-
ter.contactors*)
1.4 Wiring for RESET key
monitoring 3.2 Jumper
2 Two-Channel Emer-
gency Stop , with
cross monitoring and
manual Start
3.3 Without RESET key monitoring
2.1 RESET 46 NO safety contacts
2.2 Feedback circuit
(external contactors*) 54 NC control contacts
2.3 Without RESET key
monitoring 6Supply voltage PE = only for AC

Safety Switching Devices
Emergency-Stop Relay
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Application Example Two-Channel E-Stop Application with Cross Monitoring ,
Manual START and RESET Switch Monitoring (anti tie-down)
This application example shows the necessary connections for the
monitoring of the RESET switch. For this E-Stop application the
switch has to be connected to terminals S12/S34andterminalsY1/
S37havetobejumpered.Inthiscasethedeviceisenabledonlywhenthe
RESETswitchisclosedandreleased (fallingedgeofthesignal).This
featureallowsamanualSTARTofthedevice. The two-channel E-Stop
control circuit switches off the device even if one of the two contacts
in the E-Stop pushbutton does not open.
If a fault occurs ( i.e. the E-Stop contact connected to terminal S22
does not open), the second (redundant) contact S12 activates the
safety circuit. The 6 enabling current paths open, the control con-
tacts 71/72, 81/82 close and 91/92, 01/02 stay open. In case of a
short circuit in the lines leading to the E-Stop pushbutton, the inter-
nal supply voltage at S11, S21 is short circuited (cross monitoring).
The relays K1, K2 switch back to their off position and the electronic
protective fuse is triggered. If a line short circuit occurs in the RE-
SET switch after the device has been activated, it will be recognized
by the cyclical self-test when reactivating the device. This will inhibit
the enabling current paths (output safety contacts) to close again.
If the number of enabling current paths is not sufficient , external
contactors can be used for expansion ( 2 in this example). They are
driven through one of the enabling current paths of the device. The
function of the external contactors is monitored by their own NC
contacts connected in series to the feedback circuit Y1/Y2. The
contactors K4 and K5 must have positive guided contacts.
Two-Channel Protective Gate Application with Cross Monitoring
and Automatic Start
This sliding protective gate applications shows the necessary con-
nections for an automatic START (without monitoring of the RESET
switch). Terminals S12 and S34 have to be connected, terminal S37
stay open. The position of the sliding protective gate is monitored via
channel 1 (S12) and channel 2 (S22). The SNO 2012-xx is activated
by the automatic START. If the sliding protective gate is opened the
E-Stop relay goes back to its off-position (the 6 enabling current
paths open and the 4 control contacts close). When the protective
gate is closed again, the device is reactivated by the automatic
START.
The two-channel control circuit allows the synchronous check of the
position switches. The synchronous time is performed when closing
contact S1 (terminals S11/S12) before contact S2 (terminals
S21/S22). If contact S2 is closed before contact S1 the synchronous
time is tS= ∞.

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Emergency-Stop Relay
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Technical data
Supply
Rated voltage UNDC 24 V AC 24 V AC 115 V AC 120 V AC 230 V
Rated power AC -4,5 VA 4,5 VA 4,5 VA 4,5 VA
Rated Power DC/AC 2,4 W 4,2 W 4,2 W 4,2 W 4,2 W
Rated frequency 50 Hz to 60 Hz
Operating range 0,8 to 1,1 x UN
Residual ripple 2,4 VSS
Buffering during voltage dips ≤200 ms (only with DC design)
Control circuit
Isolation between A1/A2 and S11/S33, S21 only with AC design
Rated output voltage only to supply the inputs Y2, Y3, S12, S22 DC 24 V
Maximum voltage DC version / AC version DC 24 V / DC ≤40 V
AC short circuit protected transformerFuse DC PTC resistance, response time 500 ms / recovery time 2000 ms
Responce time tA1 / Release time tR/ Minimum switch-on time tM300 ms / ≤60 ms / ≥200 ms
Responce time tA2 / Release time tR/ Simultaneity check tS500 ms / ≤60 ms / 500 ms
Recovery time tW≥500 ms
Input voltage range DC 16,8 V to DC 26,4 V
Admissible test pulse time / test frequency 1000 µs / 10 s-1
Output circuit
Contacts 6 NO safety contacts positively driven, 4 NC control contacts positively
driven
Switching voltage UnAC/DC 230 V
Max. rated current In / safety contact 6 A
Max. total current for all contacts 24 A
Application category according EN 60947--5--1:1991 AC--15: Ue230 V, Ie3 A, DC--13: Ue24 V, Ie2 A
Short-circuit protection max. 6 A fuse element type gG
General data
Test voltage 300 V
Rated surge voltage 4 kV
Protection degree Housing/Terminals acc. DIN VDE 0470 Teil 1:11.92 IP 40 / IP 20
Isolation Creepage and clearance between circuits acc. VDE 0110 part 1, 2 :
01.89
Contamination level 3 external, 2 internal
Ambient temperature working range / storage range -25°C to +55°C / -25°C to +75°C
Weight 0,8 kg
Connection datas
Cross sections 2 x 0,75 mm2to 2,5 mm2or
1 x 0,75 mm2to 2,5 mm2single-wired or
2 x 0,5 mm2to 1,5 mm2fine-wired with connector sleeve or
1 x 0,5 mm2to 1,5 mm2fine-wired with connector sleeve
Screw max. tightening torque 0,8 to 1 Nm
For UL and CSA approvals only
Cross section AWG 18 - 16 use copper conductors 60/75°C only
Screw max. tightening torque 7 in-lbs
Please refer to the main SCHLEICHER catalogue 2 for further technical details.

Safety Switching Devices
Emergency-Stop Relay
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Assembly
A
Set the guide (1), of the unit on to the top-hat rail (2) at a slight angle.(DIN rail: 35 mm according to
EN 50022).
B
Press the unit onto the DIN rail, until the latch (3) snaps into place
Disassembly
C
Insert a screw driver into the latch.
D
Release the unit by turning or levering the screw driver.
E
Tilt the unit. Remove the unit from the DIN rail.
Dimension Diagram
Subject to Change
SCHLEICHER Electronic
GmbH & Co. KG
Pichelswerderstraße 3-5
D-13597 Berlin
Ph +49.30.33005.0
Fx +49.30.33005.344
Hotline [phone]
www.schleicher-electronic.com
[email protected]