Block a beam of light and then clear all beams.
The output relay should remain off (interlock effective), and the yellow start ready indicator light should light up.
Press the start button (short-circuit terminals 3-4, 0.05~1 second).
The output relay should be turned on, and the yellow indicator light should be off.
5.4 Test Input Function
Ensure that all beams are unobstructed. If in interlock mode, perform the startup enable first to turn on the output.
Short circuit terminals 1-2 (test input).
The output relay should be immediately turned off; After disconnecting the short circuit, the system should be reset and restarted.
5.5 Relay monitoring function test (if enabled)
Disconnect terminal 23 or 24.
Power on the control unit.
The digital display should show ". F", indicating that the relay monitoring is activated.
The fault was resolved after reconnection.
5.6 Static emergency stop test
Close all emergency stop switches, ensure the beam is unobstructed, execute the start enable, and the safety output should be turned on.
Operate any emergency stop switch (disconnect circuit), the safety output should be immediately turned off, and the digital display should not show any faults.
Repeat the test for each emergency stop switch.
5.7 Pulse Emergency Stop Test
The method is the same as static emergency stop, but additionally confirm that the DIP switch is in position XX11 XX11.
Chapter 6: Indicator lights and fault diagnosis
6.1 Internal indicator lights of control unit
LED/Display Meaning
OSSD red safety output shutdown
OSSD green safety output connected
E1-E4 yellow constant light corresponds to smooth channel beam
E1-E4 yellow flashing beam is unobstructed but lacks stability reserve
E1-E4 extinguishing beam obstructed or emergency stop circuit disconnected
7-segment digital tube clockwise scrolling light protection area is unobstructed, OSSD is turned on (running light)
The digital display shows that the protected area of "0" is obstructed
The digital display shows that the "1" protection area is unobstructed but OSSD is turned off, waiting for startup
The digital display shows "2" system malfunction
The digital display shows that the "P" DIP switch is set incorrectly or is currently being set
The digital display shows that the "E" transmitter is short circuited or the receiver is faulty
The digital display shows "F" external relay fault (relay monitoring)
The digital display shows a synchronous fault in the "8" emergency stop channel
Digital tube decimal point flashing fault status
6.2 Common Troubleshooting
Possible causes of malfunction, operator actions
All components have no indicator lights, power failure check, power supply
External OSSD indicator light does not light up, wiring error or LED damage. Check wiring
The start ready indicator light is not on, and there is a wiring problem. Check terminals 15-16
The activation of the ineffective beam is obstructed; Or check the E1-E4 indicator lights for wiring errors of the start button; If the start ready light is on, check the button circuit
Digital tube displays "2" transmitter installation issue. Check the wiring and alignment of the transmitter
The digital display shows that the "F" relay monitoring circuit is disconnected. Check the external relay and its normally closed contact series circuit
The digital display shows "0" and cannot clear the obstruction of the light beam or the disconnection of the emergency stop circuit. Check the corresponding channel receiving indication; If it is in emergency stop mode, check the status of the emergency stop switch
The digital display shows a short circuit in the "E" receiver or interference from adjacent light curtains. Check the wiring of the receiver; Ensure that the light curtains of different control units do not illuminate each other
An output cannot be connected, and the fuse is blown. Check and replace the T2A fuse
Check the contact of the emergency stop switch for the simultaneous loss of the "8" emergency stop channel displayed on the digital display; If pulse mode is used but DIP is set to static, the settings need to be changed
Note: In high-frequency electromagnetic fields (>10 V/m), the SLVA-4Kplus output may accidentally switch to a safe state.

Chapter 7: Summary of Technical Data
7.1 Security Level
Type 4 (EN 61496-1)
Category 4 (EN ISO 13849-1)
PL e
SIL 3 (IEC 61508)
7.2 Electrical Data
Power version, voltage range, power consumption, current consumption
230VAC 195~253VAC, 48~62Hz 13W ≤50mA
115VAC 98~127VAC, 48~62Hz 13W ≤100mA
24VDC 20.4~27.6VDC 7W ≤220mA
24VAC/DC (2528) 21.6~26.4VAC/DC 7W ≤220mA
Response time: 40 ms (fixed)
Start enable/fault reset signal duration: 0.05~1 second
Relay monitoring detection delay: 200 ms
Emergency stop simultaneous fault detection delay: 2 seconds
7.3 Safety output contact capacity
Switching voltage: 20-230V AC/DC
Switching current AC: 0.01~2A
Switching current DC: Refer to the load curve (resistive load approximately 2A/24VDC, inductive load requires derating)
Contact protection: Internal T2A fuse
Switching frequency: maximum once per second