Assembly / What's Included

• Dual palm button housing
• Matched anti tie down safety relay with redundant, force guided contacts
• A wiring diagram for your safety control voltage
• Installation, reset, and safety distance guidance documentation
• An optional pedestal stand and mounting hardware are available for floor mounted stations. 

Output & Connection Options

• Relay output touch buttons, required for two hand safety applications, available in low voltage (10 to 40VDC / 20 to 30VAC) or full voltage (100 to 240VAC) input types
• Transistor/PNP output touch buttons are available for general sensing use but are not used in two hand safety configurations; the anti tie down safety relay must pair with relay output touch buttons only
• General Purpose devices connect via 4 pin or 5 pin quick disconnect, or 6 ft / 24 ft cabled options
• Heavy Industrial devices use an 8 position terminal block connection, wire range #22 to 12 AWG, 9 lb·in (1 N·m) tightening torque
• Mounting hole sizes of 22.5 mm or 30.5 mm, flush or surface mount, with an optional guard

Environmental Ratings

• Degree of Protection: Type 4/4X/13, IP66, tested to 1200 psi washdown (General Purpose); Type 4/13, IP66 (Heavy Industrial)
• Operating Temperature: -25°C to +55°C (-13°F to 131°F)
• Storage Temperature: -40°C to +85°C (-40°F to 185°F)
• Humidity: up to 95% RH from 25°C to 50°C (77°F to 122°F), full operation
• Vibration tested to 10 G with 1.52 mm displacement; mechanical shock tested to 100 G

Applicable Safety Standards

• CSA 22.2, No. 14
• EN50081-2
• EN60204-1
• EN60954-1
• EN61000-6-2
• EN/IEC 60947-5-1
• UL 508

Download the Technical Data Sheet

Activation & Timing Issues

Machine won't cycle even with both hands on the buttons

• Confirm both buttons are pressed within the anti tie down relay's timing window and held continuously
• Check for a tied down or jammed button that could trigger the anti tie down fault condition
• Verify the correct safety relay (440R-D23171, 440R-D23169, or 440R-D23168) is installed for your system voltage
• Inspect wiring between the touch buttons and the safety relay for loose or damaged connections

Diagnostic LED & Status Issues

Button LED is blinking or button won't respond

• A blink pattern at power up usually means the button was touched during startup; remove your hand and wait about 10 seconds for the device to resume
• A different blink pattern means the button detected excessive electrical noise (above 20V/m); the device resumes automatically once the noise source is cleared
• A third blink pattern signals a conductive film, such as coolant or oil, building up on the sensing surface; clean the surface and the device will resume
• If the LED shows no activity at all, check incoming power at the terminal block or quick disconnect connector

Response Time & Relay Output Issues

Delay before machine starts, or machine doesn't stop as expected

• Confirm response time is within the rated 76 ms on / 60 ms off specification
• Check relay contacts for wear if the touch buttons are approaching their rated operation count (200,000 for General Purpose, 150,000 for Heavy Industrial relay output)
• Verify the safety relay's monitored reset and redundant outputs are functioning
• Test for welded or shorted contacts per the safety relay's fault detection routine

Wiring & Connection Issues

Intermittent operation or no output signal

• Recheck wire range and terminations; Heavy Industrial units use an 8 position terminal block, General Purpose units use 4 pin or 5 pin quick disconnect connectors
• Confirm tightening torque on terminal connections is correct
• Inspect cabled versions for cuts, pinches, or strain at the connector
• Verify common wiring is correct if isolated commons are required

Environmental & Contamination Issues

Degraded or inconsistent performance over time

• Clean the sensing surface regularly, especially in washdown or high oil/coolant environments
• Confirm the enclosure rating (Type 4/4X/13, IP66) matches the actual operating environment
• Check gasket condition on Heavy Industrial units for signs of wear
• Verify ambient temperature and humidity remain within rated limits

Mechanical & Housing Issues

Physical damage, guard problems, or mounting issues

• Inspect the optional guard for damage that could block or interfere with the touch surface
• Confirm mounting hardware is tight and the pedestal stand, if used, hasn't shifted
• Check housing material for cracks or wear from vibration or shock
• Verify the button surface still conforms properly and shows no visible sensor damage

Safety Compliance & Selection

System design concerns or audit findings

• Confirm the safety relay's rated category (Category 3/PLd or Category 4/PLe) matches your machine's required performance level
• Ensure hand spacing and button placement meet ISO 13851 safe distance requirements
• Verify relay output touch buttons, not transistor/PNP output, are used for the two hand safety function
• Confirm periodic function testing is documented per your safety program

Preventive Maintenance

To avoid recurring issues:

• Clean touch button surfaces on a regular schedule, especially in washdown environments
• Inspect wiring, terminal connections, and cable strain relief periodically
• Track relay output operation counts against rated life (200,000 or 150,000 operations)
• Confirm anti tie down timing and safety distance settings haven't drifted from commissioning

Fault Tracking & Continuous Improvement

• Log every fault or trip, including which diagnostic LED pattern was shown and the operating conditions at the time
• Look for patterns, such as repeated noise faults tied to a specific piece of nearby equipment
• Use fault history to plan relay and button replacement before reaching rated operation limits