Watlow PM LEGACY ™ Limit controller

Profibus DP (Slot B): The terminals are VP (+5Vdc), B (T+/R+), A (T -/R -), DG (digital ground), trB (terminal resistance B), trA (terminal resistance A), and require Profibus dedicated cables. The end device needs to be equipped with a terminal resistance (150 Ω), address 0-126, and a maximum transmission distance of 1200 meters.

Wiring precautions: All wiring must comply with NEC or local safety standards, and power-off operation is required; The wire specification is 0.0507-3.30mm ² (30-12 AWG) single stranded wire, or two 1.31mm ² (16 AWG) wires, with a terminal torque of 0.56 Nm (5.0 inch pounds); Unused terminals must not be wired to prevent short circuits; Analog inputs, digital I/O, switch DC outputs, and process outputs must be electrically isolated to prevent grounding loops; When switching inductive loads (such as relay coils and solenoid valves), it is necessary to install an RC suppressor (Watlow recommended model 0804-0147-0000) to avoid electromagnetic interference damaging the equipment.

Operation and Configuration Guide

（1） Page navigation and basic operations

page switching

Home Page: By default, it displays process values (PV) and limit states (safE/faiL), which can be returned from any page by long pressing the Reset button for 2 seconds.

Operations Page: Press and hold the Up+Down key for 3 seconds from the home page to enter, displaying parameters that can be monitored/modified such as analog input values, limit status, digital I/O status, alarm status, etc. Use the Up/Down key to switch menus, the Advance key to enter submenus, and the Reset key to return to the previous level or home page.

Setup Page: Press and hold the Up+Down key for 6 seconds from the homepage to enter (hold down continuously until "SEt" is displayed), used to configure input, output, alarm, communication, global parameters, etc. The operation logic is consistent with the operation page, and some parameters need to be restarted to take effect after modification.

Factory Page: Press and hold the Advance+Reset button for 6 seconds from the homepage to enter. It is used for customizing the homepage, calibration, security settings (password/lock), diagnosis, etc. Caution is required when operating, and some functions (such as calibration) require professional personnel to perform.

Button Function

Up/Down keys: Modify writable parameter values (such as limit settings) on the homepage, and switch parameters/options in the menu.

Advance button: Switch display parameters on the homepage (such as low limit → high limit), enter submenus in the menu or confirm the selection.

Reset button: Reset limit (after troubleshooting), clear alarm (latch alarm), return to the previous page, long press for 2 seconds to return to the home page.

Function key (Fn, only 1/16 DIN): a programmable key that can configure functions (such as limit reset, alarm mute, user settings recovery, etc.) in the "Setup Page Function Key Menu", supporting level triggering or edge triggering.

（2） Key parameter configuration

Home page customization: Enter the "Factory Page Custod Menu (CuSt)" and select 20 parameters to add to the homepage (such as analog input values, limit settings, alarm status, etc.). Parameter instances (such as alarms 1-4) need to be selected separately; Set the number of display pairs (1-10) through "Setup Page Global Menu-d-prs (Display Pairs)", and set the automatic switching time (0-60 seconds, 0 is not automatic switching) through "d.ti (Display Time)". Custom homepage parameters will be updated synchronously after modification on the original page (operation page/settings page), and vice versa.

Simulated input configuration (Setup Page Analog Input Menu)

Sensor type (sEn): Select the type that matches the connected device (such as thermocouple J-type, RTD 100 Ω, 0-20mA, etc.), "off" indicates disabling the input.

Linearization (Lin): Only thermocouples need to be set, select the corresponding linearization curve for the thermocouple type (such as J, K, T, etc.).

Scaling and Range (s.Lo/s.hi, r.Lo/r.hi): Process inputs need to be set, for example, 4-20mA corresponds to 0-100 ℃, so s.Lo=4.00mA, s.hi=20.00mA, r.Lo=0.0 ℃, r.hi=100.0 ℃; The scaling value is the input signal range, and the range value is the display/control range. It supports reverse scaling (e.g. 50psi corresponds to 4mA, 10psi corresponds to 20mA).

Filtering (fiL): Set the filtering time constant (0.0-60.0 seconds, default 0.5 seconds) to smooth the input signal, reduce noise interference, and filter without affecting the limit sensor signal.

Calibration offset (i.Ca): Used to compensate for sensor errors or lead resistance, it can be modified in the "Operations Page Analog Input Menu" (-1999.000-9999.000 ° F/° C), with positive offset increasing the input value and negative offset decreasing the input value.

Set Page Limit Menu

Limit Sides (L.sd): Select "high", "Lo І", or "both" to determine the upper, lower, or both limits of the monitoring process value.

Limit setting value (Lh. s/LL. s): Set the high/low limit trigger value (-1999.000-9999.000 ° F/° C, default 0.0 ° F or -18.0 ° C), which needs to be set according to process requirements, for example, the high limit of the heating equipment is set to 200 ℃ and the low limit is set to 50 ℃.