L42

The L22, L62, and L42 FM Approved High Limit Controls are engineered to provide reliable, code-compliant safety protection in industrial ovens, furnaces, and thermal processing systems. With FM approval, UL/cUL listing, and NFPA 86 compliance, these limit controllers are trusted by OEMs, panel builders, and process engineers who need both safety and flexibility.

Cost-Effective

High Performance Without the Price Tag!

Easy to Use

Simple Set-Up and Use

Short Lead Times

Average Days to Ship 2-3 Business Days

The L22 DIN rail mount, L62 1/16 DIN, and L42 1/4 DIN models give users multiple form factors with consistent feature sets, making them ideal for integration into new systems or retrofit projects.

Key Features & Benefits

Flexible Universal Inputs

The L-Series controllers accept a wide range of analog input signals, including:
– Thermocouples
– RTDs
– mA signals
– VDC and mV inputs

This makes the controllers highly adaptable across industries such as food & beverage, aerospace, semiconductor, medical, and energy.

Multiple Output Options

– Output #1 (Standard): Always a latching high-limit output for safety.
– Output #2 (Optional): Configurable as latching or non-latching, with options for self-clearing alarms or annunciator silence logic.
– Output #3 (L62 & L42 only): Adds even more flexibility for alarm and safety signaling.

Digital outputs include:
– Relay (2A/240 VAC SPST)
– SSR driver outputs (5VDC/30mA or 14VDC/40mA)
– Transmitter power supply options (5 VDC, 12 VDC, or 20 VDC isolated)

Power-On Logic Options

The L-Series controllers allow users to configure startup behavior based on process requirements:
– NoRM (Normal): Returns to normal operation at startup.
– RSt (Reset Required): Forces a manual reset after power-up for added safety.
– NoR.L (Normal-Latch): Returns to its prior state before power was removed, latching if in alarm condition.

This flexibility ensures compliance with diverse safety protocols and corporate standards.

Dual Display for Operator Confidence

– Upper Display: Always shows the Process Variable (PV) (temperature).
– Lower Display: Configurable to show Setpoint (SP) or the word SAFE when not in alarm state.
– Alarm State: Lower display defaults to Setpoint, ensuring critical visibility.

This design gives operators instant, at-a-glance status updates.

Event Input (EI) Options

These programmable EI options allow high customization for complex safety systems.

– L22: One digital Event Input.
– L62 & L42: Two digital Event Inputs.

Available functions include:
– Remote lock (parameter protection)
– Remote reset (manual reset from remote switch)
– Secondary and tertiary high/low limit setpoints (HSP2, HSP3, LSP2, LSP3)
– Reset individual alarms or all alarms (RS.A1, RS.A2, RS.A3, RS.Ao)
– Cancel alarm latch (CA.LH)

Communication & Integration

– RS485 Modbus communications provide full parameter access for remote monitoring and control.
– Linear retransmission allows analog output of PV or SP values.
– Compatible with PLC, SCADA, and DCS systems.

Specifications

Power Input:
- 90-250VAC 47-63 HZ
- 11-40 VDC / 20-28 VAC (optional)
Input sample rate – 5 scans/second
Analog Inputs:
- Universal Analog Input, Thermocouple, RTD, mA, VDC and mV.
Event Inputs (optional): The L22 offers 1 with L62 & L42 offering 2 Event Inputs.
- Functions Listed Below with descriptions
  - LoCK: Selects the remote lock function.
  - R.RSt Selects the remote reset function.
  - H.SP2 Activates high limit set point 2.
  - L.SP2 Activates low limit set point 2
  - H.L.S2 Activates high and low limit set point 2
  - H.SP3 Activates high limit set point 3.
  - L.SP3 Activates low limit set point 3.
  - H.SP3 Activates high limit set point 3.
  - H.L.S3 Activates high and low limit set point 3.
  - RS.A1 Selects the reset alarm 1 function
  - RS.A2 Selects the reset alarm 2 function.
  - RS.A3 Selects the reset alarm 3 function.
  - RS.Ao Selects the reset all alarms function.
  - CA.LH Selects the cancel alarm latch function
Limit Control Output #1 – Latching: Configurable as High Alarm, Low Alarm or combination High-Low Alarm Setpoint with one digital output. Available Digital Outputs:
- Relay: 2A/240 VAC resistive [SPST]
- SSR Driver: 5VDC/30mA or 14VDC/40mA
Output #2 is available with one of the following options: Digital Output [relay, triac or ssr driver] transmitter power supply, communications.
- Digital Outputs are same as output #1
- Transmitter Power Supply [Isolated];
  - 20 VDC/25mA
  - 12 VDC/40mA
  - 5 VDC/80mA
Output #3 is limited to L62 & L42
- L22: Not available
- L62: Relay 2A form A SPST is mutually exclusive with Communications Retransmission
- L42: Relay 2A form A SPST
Communications: not mutually exclusive, all may be ordered except for L62 with Output #3
- Digital Event Input (EI): L22 one EI with L62 & L42 two EI
- RS485 Modbus Communication with access to all parameters.
- Retransmission Linear of Process Value (temperature) or Setpoint Value
Configurable Display when not in alarm condition Setpoint or when not in alarm condition the word SAFE.
- When in Alarm display defaults to SP (setpoint) with output 1 latched closed and front panel Out1 annunciation energized.