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© PHOENIX CONTACT - 08/2008103465_en_00 INTERFACE MACX MCR-EX-SL-NAM-2RO(-SP) Data sheet 1D e s c r i p t i o n The NAMUR MACX MCR-EX-SL-NAM-2RO(-SP) isolating amplifier has been designed for intrinsically safe operation of the proximity sensors (as per EN 60947-5-6 (NAMUR)) and the floating and resistance circuit mechanical contacts installed in the Ex area. The input circuit is monitored for line faults (breakage and short circuit (LFD)) (can be switched on/off). Errors are indicated via a red flashing LED (as per NE 44) and the relevant output relay is de-energized. Error messages are also transmitted to the power and error evaluation module via the DIN rail connector. The output side has two N/O contact relays. Both can be operated as signal outputs. Output 2 can also be used as an error message output (can be adjusted via the DIP switch). The switch can be used to set the direction (open or closed circuit current behavior). The relay status is indicated via a yellow LED. The modules can be installed in zone 2 with the "n" (EN 60079-15) protection type.
1.1 Properties
– Input for NAMUR proximity se nsor or switch, [Ex ia] IIC – Two relay signal outputs (N/O contact); output 2 can be used as an error message output – Line fault detection (LFD) – Option of phase reversal – 3-way electrical isolation – SIL 2 according to EN 61508 – Installation in Zone 2 permissible – Power supply and error message possible via the DIN rail connector – With screw (MACX MCR-EX-SL-NAM-2RO) or spring-cage connection (MACX MCR-EX-SL-NAM-2RO-SP) WARNING: Explosion hazard The module is an associated item of electrical equipment for intrinsically safe circuits. It is designed for use in zone 2, if specific conditions are observed. When installing and operating the device, the applicable safety directives (including national safety directives), accident prevention regulations, as well as general technical regulations, must be observed. WARNING: Explosion hazard Be sure to observe the safety regulations and installation notes on page 5. Make sure you always use the latest documentation. It can be downloaded at www.download.phoenixcontact.com A conversion table is available on the Internet at This data sheet is valid for all products listed on the following page: Intrinsically safe NAMUR isolating amplifier with two relay outputs
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 2 Table of contents 2O r d e r i n g d a t a
3 Technical data
NAMUR isolating amplifiers Description Type Order No. Pcs./Pkt. Intrinsically safe NAMUR isolating amplifier, with two relay outputs and screw connection MACX MCR-EX-SL-NAM-2RO 2865450 1 Intrinsically safe NAMUR isolating amplifier, with two relay outputs and spring-cage connection MACX MCR-EX-SL-NAM-2RO-SP 2924061 1 Accessories Description Type Order No. Pcs./Pkt. DIN rail connector (T-BUS), 5-pos., for bridging the supply voltage, can be snapped onto NS 35/... DIN rails according to EN 60715 ME 6.2 TBUS-2 1.5/5-ST-3.81 GN 2869728 10 Power and error evaluation module, including the relevant DIN rail connector ME 17.5 TBUS 1.5/5-ST-3.81 GN Screw connection Spring-cage connection MACX MCR-PTB MACX MCR-PTB-SP 2865625 2924184 For additional accessories, please refer to the "INTERFACE" catalog from Phoenix Contact. Input Input Intrinsically safe, designed for protection type Ex-i [Ex ia] IIC Available input sources – NAMUR proximity switches according to EN 60947-5-6 or – Switch contacts wi th open circuit (not for safety-related applications, SIL 2) or – Switch contacts with resistance circuit Switching hysteresis < 0.2 mA
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 3 Control circuit Non-load voltage 8 V DC ±10% Switching points according to EN 60947-5-6 I < 1.2 mA (blocking) I > 2.1 mA (conductive) Line fault detection Break 0.05 mA < I IN < 0.35 mA Short circuit 100 Ω < Rsensor < 360 Ω Activated/deactivated via DIP switch Switching output Switching output Relay, 2 x N/O contacts Switching behavior Can be inverted using DIP switch Switching frequency 20 Hz (without load) Maximum switching voltage 250 V AC (2 A) 120 V DC (0.2 A)
30 V (2 A)
Maximum switching power 500 VA Contact material AgSnO2, gold-plated Service life Mechanical 10 7 cycles Recommended minimum load 5 V/10 mA General data Supply voltage range 19.2 V DC ... 30 V DC Current consumption, maximum 30 mA (24 V DC) Power dissipation < 950 mW Electrical isolation Input/output Input/power supply Input/power supply, DIN rail connector Output 1/output 2/input, power supply, DIN rail connector
375 V (peak value according to EN 60079-11)
300 Vrms (rated insulation voltage, surge voltage category II, pollution
degree 2, safe isolation as per EN 61010, EN 50178) 1.5 kV AC (50 Hz, 1 min., test voltage)
300 Vrms (rated insulation voltage, surge voltage category III; pollution
degree 2, safe isolation as per EN 61010, EN 50178) 2.5 kV AC (50 Hz, 1 min., test voltage) Ambient temperature Operation Storage/transport -20°C ... +60°C (any mounting position) -40°C ... +80°C Permissible humidity (operation) 10% ... 95% (no condensation) Status indicator Green LED (PWR, supply voltage) Red LED (LE, line errors) Yellow LED (OUT, switching state) Housing material PBT Color Green Degree of protection IP20 Width x length x height 12.5 mm x 114.5 mm x 104 mm (with connection terminal block) Inflammability class according to UL 94 V0 Design Terminal block housing for mounting on DIN rails Conformance EMC directive 2004/108/EC EN 61000-6-2, EN 61000-6-4, EN 61326-1 Ex directive (ATEX) EN 60079-0, EN 60079-11, EN 60079-15
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 4 Safety data according to ATEX for intrinsically safe circuits Maximum voltage Uo 9.6 V Maximum current Io 10 mA Maximum power Po 25 mW Maximum inner inductance Li Maximum inner capacitance Ci Negligible 11 nF Gas group IIC IIB Maximum external inductance Lo 100 mH 5 mH 1 mH 10 μH 100 mH 5 mH 1 mH 10 μH Safety-related maximum voltage Um 253 V AC (125 V DC) Certificates ATEX X II (1) GD [Ex ia] IIC, IIB IBExU 07 ATEX 1069 X II (3) G Ex nAC II T4 X IECEx approval [Ex ia] IIC; [Ex ia D]; Ex nAC IIC T4 IECEx IBE 08.0001X UL USA/Canada Applied for Functional safety (SIL) SIL 2 according to EN 61508 Connection data MACX MCR-EX-SL-NAM-2RO Conductor cross-section Solid (minimum/maximum) Stranded (minimum/maximum) AWG/kcmil (minimum/maximum) 0.2 mm 2/2.5 mm2 0.2 mm2/2.5 mm2 Stripping length 7 mm Connection method Pluggable screw connection Tightening torque 0.5 Nm, minimum/0.6 Nm, maximum Connection data MACX MCR-EX-SL-NAM-2RO-SP Conductor cross-section Solid (minimum/maximum) Stranded (minimum/maximum) AWG/kcmil (minimum/maximum) 0.2 mm 2/1.5 mm2 0.2 mm2/1.5 mm2 Stripping length 8 mm Connection method Spring-cage connection
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 5
4 Safety regulations and installation notes
4.1 Installation and operation
Follow the installation instructions. When installing and operating the device, the applicable safety directives (including national safety directives), accident prevention regulations, as well as general technical regulations must be observed. Do not repair the device yourself, but replace it with an equivalent device. Repairs may only be carried out by the manufacturer. Install the device in a suitable housing with a suitable degree of protection in accordance with IEC 60529 in order to protect it from mechanical and electrical damage. For the safety data, please refer to the operating instructions and certificates (EC type-examination, other approvals, if necessary).
4.2 Safety regulations for installation in potentially
Regulations for intrinsically safe circuits Installation in Zone 2 Observe the specified conditions for use in potentially explosive areas. Installation in areas with a danger of dust explosions Connection to the intrinsically safe circuit in areas with a danger of dust explosions (zones 20, 21, and 22) is only permitted if the equipment connected to this circuit is approved for this zone (e.g., category 1D, 2D or 3D). NOTE: Installation, operation, and maintenance may only be carried out by qualified specialist personnel. NOTE: The circuits inside the device must not be accessed. NOTE: The device is designed to meet IP20 protection when: – It is installed outside potentially explosive areas. – The environment is clean and dry. NOTE: The load connected to the relay outputs should be limited to the values listed in the technical data. WARNING: Explosion hazard When carrying out measurements on the intrinsically safe side, be sure to observe the relevant regulations regarding the connection of intrinsically safe equipment. Only use devices approved for use in intrinsically safe circuits. WARNING: Explosion hazard If the device has been used in non- intrinsically safe circuits, it must not be used again in intrinsically safe circuits. Clearly label the module as being non-intrinsically safe. WARNING: Explosion hazard The device is associated equipment of the "Ex-i" protection type and suitable for installation in Zone 2. WARNING: Explosion hazard Install the device in suitable housing with a minimum of IP54 degree of protection. Observe the requirements of IEC 60079-14/ EN 60079-14, e.g., steel housing with a wall thickness of 3 mm. WARNING: Explosion hazard Disconnect the block power supply before: – Snapping it on or disconnecting it. – Connecting or disconnecting cables of non- intrinsically safe circuits. WARNING: Explosion hazard Only use category 3G modules (ATEX 94/9/EC). WARNING: Explosion hazard The device is not designed for installation in areas with a danger of dust explosions.
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 6
4.3 Use in safety-related applications (SIL 2)
When using the MACX MCR-EX-SL-NAM-2RO(-SP) in safety-related applications, observe the instructions in Section 9, as the requirements differ for safety-related functions.
5 Installation
5.1 Basic circuit diagram
Figure 1 Basic circuit diagram with connection terminal blocks
5.2 Design
1 COMBICON plug connectors
2 PWR LED (green), for indicating the power supply
3 LED LF1/LF2 (red), for indicating line faults on the
4 LED OUT1 (yellow), for indicating switching state of
5 LED OUT2 (yellow), for indicating switching state of
6 Switch DIP1 ... DIP4
7 Metal lock for fixing on the DIN rail
8 Connection option for DIN rail connector
5.3 Dimensions
Figure 3 Dimensions (in mm) NOTE: Electrostatic discharge The device contains components that can be damaged or destroyed by electrostatic discharge. When handling the device, observe the necessary safety precautions against electrostatic discharge (ESD) according to EN 61340-5-1 and EN 61340-5-2. OUT113 OUT2 IN OUT 4.2 4.1 3.2 3.1 2.2 2.1 1.2 1.1 GND +24V Power Zone 0,1,2 Div. 1,2 Zone 2 Div. 2 Faultsignal GND +24VLFD Ex area Safe area PWR LF OUT1 OUT2 1.1 1.2 2.1 2.2 3.1 3.2 4.1 4.2 MACX MCR-EX-SL-NAM-2RO II I 99 12,5 7 114,5
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 7
5.4 Mounting
Figure 4 Assembly and removal – Mount the module on a 35 mm DIN rail according to EN 60715. – When using the DIN rail connector, first place it into the DIN rail (see A – C, Figure 4). It is used to bridge the voltage supply and for error messages. Please also ensure you observe the direction of the module and DIN rail connector when snapping into position: Snap-on foot below (2) and connector left (1). – Install the module in suitable housing to meet the requirements for the protection class. – Before startup, check that the NAMUR isolating amplifier is operating and wired correctly, especially with regard to the wiring and labeling of the intrinsically safe circuits.
5.5 Connecting the cables
– Pluggable screw terminal blocks (on MACX MCR-EX-SL-NAM-2RO); litz wires provided with ferrules. – Pluggable spring-cage terminal blocks (on MACX MCR-EX-SL-NAM-2RO-SP); litz wires provided with ferrules. – Lay intrinsically safe and no n-intrinsically safe cables separately. – Permissible cable cross-section: 0.2 mm 2 to 2.5 mm2. – Screw connection: – Insert the wire into the corresponding connection terminal block. – Use a screwdriver to tighten the screw in the opening above the connection terminal block. – Spring-cage connection: – Insert a screwdriver in the opening above the connection terminal block. – Insert the wire into the corresponding connection terminal block.
5.6 Voltage supply
The modules can be powered via the connection terminal blocks 1.1 (+24 V) and 1.2 (GND) or via the DIN rail Depending on the number of modules to be powered, the voltage is either fed via the MACX MCR-EX-SL-NAM-2RO(-SP) or the power and error evaluation module MACX MCR-PTB(-SP) on the DIN rail connector. Supply via the module Where the total current consumption of the aligned modules does not exceed 400 mA, the power can be supplied directly at the connection terminal blocks of the module. A 400 mA fuse should be connected upstream. The voltage supply is provided at the connection terminal blocks 1.1 (+24 V) and 1.2 (GND). Infeed via the power and error evaluation module MACX MCR-PTB(-SP) The supply voltage is fed in via the module MACX MCR-PTB(-SP) to the DIN rail connectors. The supply voltage can be provided as either simple or redundant. The module MACX MCR-PTB(-SP) has integrated error evaluation. An auxiliary supply failure or fuse error is registered to a relay contact and displayed via a flashing LED. Collection line faults of all modules connected via the DIN rail connectors are also signaled. WARNING: Explosion hazard If the module has been used in non- intrinsically safe circuits, it must not be used again in intrinsically safe circuits. Clearly label the module as being non-intrinsically safe. A B C NOTE: Never connect the supply voltage directly to the DIN rail connector. It is not permitted to draw power from the DIN rail connector or from individual MACX-MCR-EX modules.
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 8
6 Configuration
In the default state upon delivery, all DIP switches are set to the position "I".
6.1 Line fault detection (switch DIP2)
Line fault detection is enabled or disabled using switch DIP2. When line fault detection is enabled, the relay drops out in the event of a cable interrupt or short circuit to the sensor so that the output is set to the safe, non-conductive state. The red LED (LF) flashes. If the module is connected to a power module MACX MCR-PTB(-SP) via a DIN rail connector, a group error message is also sent to the higher-level evaluation unit via floating relay output.
6.2 Phase reversal (switch DIP1)
The phase reversal function is enabled or disabled using switch DIP1.
6.3 Output OUT2 (s witch DIP3/DIP4)
DIP1 = I Normal phase DIP1 = II Inverted phase DIP2 = I Line fault detection disabled * (Not permitted for safety-related applications, SIL 2) DIP2 = II Line fault detection enabled PWR = Supply voltage OUT1 = Switching state of relay output 1 OUT2 = Switching state of relay output 2 LF = Line fault on the sensor cable WARNING: For safety-related applications, only the switch position "DIP2 = II" is permitted. Operating range for the – Cable break alarm 50 μA > I > 350 μA – Short circuit alarm 100 Ω > R > 360 Ω NOTE: For switch contacts with open circuit (Figure 5), line fault detection (DIP2 = I) must be disabled or the corresponding resistance circuit must be provided directly at the switch contact (Figure 6, e. g. UKK 5-2R/NAMUR (Order No. 2941662) with D-UKK 3/5 (Order No. 2770024)). PWR LF OUT1 OUT2 4.1 4.2 MACX MCR-EX-SL-NAM-2R O II I Figure 5 Switch contact with open circuit (Not permitted for safety-related applications, SIL 2) Figure 6 Switch contact with resistance circuit Output relay Normal phase (I) Inverted phase (II) Switched if I > 2.1 mA I < 1.2 mA In normal position when I < 1.2 mA I > 2.1 mA DIP3 DIP4 Operating mode OUT2 X = II Signal duplicator = II = I Error indicator = II = II Disabled 10 kΩ 1 kΩ OUT1 OUT2 4.1 4.2 MA C II I
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 9
6.4 Truth table
WARNING: For safety-related applications, only the switch position "DIP2 = II" is permitted. WARNING: Only switch contacts with resistance circuit are permitted at the input for safety- related applications (see Figure 6). Sensor in Input Input circuit DIP Relay contact output (N/O contact) LED OUT LF LEDOUT1 OUT2 Switch NAMUR State 1 2 Signal duplicator Error indicator Disconnected Yellow Red Open Blocking OK I I Open Open Open Open Closed Conductive OK I I Closed Closed Open Open X Open Blocking OK II I Closed Closed Open Open X Closed Conductive OK II I Open Open Open Open Blocking OK I II Open Open Open Open Conductive OK I II Closed Closed Open Open X Any Open circuit I II Open Open Closed Open X Any Short circuit I II Open Open Closed Open X Blocking OK II II Closed Closed Open Open X Conductive OK II II Open Open Open Open Any Open circuit II II Open Open Closed Open X Any Short circuit II II Open Open Closed Open X PWR LF1 LF2 OUT1 OUT2 4.1 4.2 5.1 5.2 MACX MCR-EX-SL-2NAM II I DIP2 = I Line fault detection disabled (not permitted for safety-related applications, SIL 2) DIP2 = II Line fault detection enabled DIP1 = I Normal phase DIP1 = II Inverted phase DIP4 = II Signal duplicator DIP 3 = II + DIP4 = I Error indicator DIP 3 = II + DIP4 = II Disabled PWR LED = Supply voltage LED OUT1 = Switching st ate of relay output 1 LED OUT2 = Switching state of relay output 2 LF LED = Line fault on the sensor cable
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 10
7 Comparison of safety data
For the values for Uo, Io, Po, Lo and Co, please refer to "Safety data according to ATEX for intrinsically safe circuits" on page 4. Requirements for intrinsic safety (simple circuits): Ui ≥ Uo Ii ≥ Io Pi ≥ Po Li + Lc ≤ Lo Ci + Cc ≤ Co (Lc and Cc depend on the cables/lines used). 8S w i t c h o n WARNING: Explosion hazard Compare the safety data before connecting a module located in the intrinsically safe area to the MACX MCR-EX-SL-NAM-2RO(-SP). Field devices: U i, Ii, Pi, Li, Ci Isolation amplifier: U o, Io, Po, Lo, Co NOTE: Around 5 seconds after switching on the main power, the module is ready for use. It depends on the operating conditions as to whether the module reaches its specified accuracy immediately or whether there is a warm-up period. The greatest possible accuracy is achieved when the unit has been running for around 2 hours.
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 PHOENIX CONTACT 11
9 Safety-related applications (SIL 2)
9.1 Wiring
Permitted for safety-related applications: – NAMUR sensor (according to EN 60947-5-6) – Switch contact with resistance circuit (1 k Ω serial and 10 kΩ parallel (tolerance ±10%)) (Note: The resistance circuit regulates the behavior of a NAMUR sensor) Output The safety-related function at the output is dependent on the position of switch DIP1.
9.2 Diagnostic functi on of switch DIP2
For safety applications, line fault detection is enabled, i.e., the DIP2 switch is in the "II" position. When line fault detection is enabled, the red LED indicates any faults that occur. If a line fault is detected, the output is disabled ("non-conductive"). This behavior is not dependent on the position of the DIP1, DIP3 and DIP4 switches.
9.3 Safe state
The "safe state" means that the output is in a non-conductive state, i.e., the relay contact is open.
9.4 Response times
Following a state change at the input, the output enters the safe state in ≤ 40 ms.
9.5 Operating mode of the safety function
Operating mode as per EN 61508: "Low demand mode"
9.6 Failure behavior and required response
- The safe state is entered in the event that a line fault is detected or the supply voltage fails (see Section 9.3). 2. The safe state is reached by removing the connection terminal blocks. Startup and restart WARNING: Switch contacts without resistance circuit are not permitted for safety-related applications. I = Normal operation In the event of a 0-signal (NAMUR sensor high resistance, therefore lower current in the input circuit) the output (N/O contact) switches to the "non-conductive" state. II = Inverse function In the event of a 1-signal at the input, the output switches to the "non-conductive" state. WARNING: The "DIP 2 = I" switch position is not permitted for safety-related applications. Behavior Description Startup or restart of the device The output enters the state without oscillation (according to the truth table on page 9). A reset is not required. What happens when a line fault is detected and what must the user do? The fault is indicated by the red LED and the output enters the "non-conductive" state regardless of the input signal and the operating mode (normal or inverse mode). The user must remove the line fault (short circuit or break in the sensor cable). The device output is not blocked when fault detection is triggered (no lock or reset). Undefined line states that occur during repairs can switch the output. The user must prevent this from happening by disconnecting the supply voltage or removing the connection terminal blocks. Other options that have the same result and do not present an additional hazard are permitted. The line fault is removed. The user must ensure that a defi ned state is entered using the truth table on page 9. The device is restarted in the same way as during initial startup. The device then behaves as described under "Startup or restart of the device“.
MACX MCR-EX-SL-NAM-2RO(-SP) 103465_en_00 12PHOENIX CONTACT GmbH & Co. KG • 32823 Blomberg • Germany • Phone: +49-(0) 5235-3-00 PHOENIX CONTACT • P.O.Box 4100 • Harrisburg • PA 17111-0100 • USA • Phone: +717-944-1300 www.phoenixcontact.com
9.7 Safety integrity requirements
– Type A device (according to EN 61508-2) – Safety Integrity Level (SIL) 1 and 2 Non-inverted operation: PFDAVG values Inverted operation: PFDAVG values The boxes marked in white mean that the calculated PFDAVG values are within the allowed range for SIL 2 according to table 2 of EN 61508-1, but do not fulfill the requirement to not claim more than 10% of this range, i.e., to be better than or equal to 1.00E-03. The boxes marked in gray mean that the calculated PFDAVG values are within the allowed range for SIL 2 according to table 2 of EN 61508-1, and do fulfill the requirement to not claim more than 10% of this range, i.e., to be better than or equal to 1.00E-03. Failure limit The operating mode is based on low demand mode. The percentage of the device at PFH/PFD for the overall safety loop is less than 10%. Figure 7 Safety loop Conditions – The failure rates of the components used remain constant throughout the period of use. – Propagation of errors by the device in the system is not taken into consideration. – The repair time (= replac ement) should take eight hours. – The failure rates of the external power supply are not taken into consideration. – The average temperature at which the device is to be used is +40°C. This is based on standard industrial conditions. The failure rates given refer to an ambient temperature of +40°C. For an ambient temperature of +60°C, you will need to multiply the failurerates by a factor of 2.5. The factor of 2.5 is based on empirical values gathered.
9.8 Proof test
- Carry out the appropriate steps to prevent incorrect use. 2. An appropriate signal is applied at the input of the MACX MCR-EX-SL-NAM-2RO in order to obtain the non-conductive state at the output. Check whether the output is non-conductive. 3. Restore the safety circuit to full functionality. 4. Return to normal operation. With this test, around 99% of possible "du" ("dangerous undetected") errors are uncovered in the repeater power supply. λsd λsu * The SU (Safe Undetected) category includes failures that do not cause a spurious trip. λdd λdu SFF† † SFF = Safe Failure Fraction DCS ‡ DC = Diagnostic Coverage (safe or dangerous) DCD
6 FIT**
** FIT = Failure in Time (1 FIT = 1 failure/109 h) 249 FIT 7 FIT 64 FIT 78% 2.4% 9% T[PROOF] = 1 year 2 years 5 years PFDAVG * = * PFD = Probability of Failure on Demand 3.09E-04 6.17E-04 1.54E-03 λsd λsu * The SU (Safe Undetected) category includes failures that do not cause a spurious trip. λdd λdu SFF† † SFF = Safe Failure Fraction DCS ‡ DC = Diagnostic Coverage DCD
1 FIT**
** FIT = Failure in Time (1 FIT = 1 failure/109 h) 248 FIT 6 FIT 62 FIT 78% 0.4% 8% T[PROOF] = 1 year 2 years 5 years PFDAVG * = * PFD = Probability of Failure on Demand 3.01E-04 6.02E-04 1.50E-03 Sensor 25% Switching amplifier < 10% Processing 15% Actuator 50%