Penn A421ABD Series User Manual (English)

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A421 Series Electronic Temperature Controls with Off-Cycle Defrost Installation Instructions

Refer to the QuickLIT website for the most up-to-date version of this document.

Applications

The A421 Series Electronic Temperature Controls are

single-stage, electronic temperature controls with a

single-pole, double-throw (SPDT) output relay.

A421 controls feature a backlit LCD with adjustable

brightness and three-button touchpad interface that

can be set up to restrict user adjustments. An LED

indicates the output relay's On/Off status.

A421 controls have simple On and Off temperature

settings for heating or cooling, an adjustable anti-short

cycle delay, temperature setback, and sensor offset

capability. The temperature control range is

40 to 212°F or -40 to 100°C.

The A421 controls are available either in Type 1

(NEMA), IP20 (CE), high-impact plastic enclosures

suitable for surface or DIN rail mounting (Figure 1)

or in Type 4X (NEMA), IP66 (CE) watertight, corrosion

resistant surface mount enclosures (Figure 2).

Dimensions

IMPORTANT: Use this A421 Series Electronic

Temperature Control only as an operating control.

Where failure or malfunction of the A421 control could

lead to personal injury or property damage to the

controlled equipment or other property, additional

precautions must be designed into the control

system. Incorporate and maintain other devices, such

as supervisory or alarm systems or safety or limit

controls, intended to warn of or protect against failure

or malfunction of the A421 control.

IMPORTANT: Utiliser ce A421 Series Electronic

Temperature Control uniquement en tant que

dispositif de régulation. Lorsqu'une défaillance ou un

dysfonctionnement du A421 control risque de

provoquer des blessures ou d'endommager

l'équipement contrôlé ou un autre équipement, la

conception du système de contrôle doit intégrer des

dispositifs de protection supplémentaires. Veiller

dans ce cas à intégrer de façon permanente

d'autres dispositifs, tels que des systèmes de

supervision ou d'alarme, ou des dispositifs de

sécurité ou de limitation, ayant une fonction

d'avertissement ou de protection en cas de

défaillance ou de dysfonctionnement du

A421 control.

Figure 1: A421 Control with Type 1 (NEMA),

IP20 Enclosure Dimensions, in. (mm)

Figure 2: A421 Control with Type 4X (NEMA),

IP66 Enclosure Dimensions, in. (mm)

A421 Series Electronic Temperature Controls with

Off-Cycle Defrost

Installation Instructions

A421ABD-x, A421AED-x

Part No. 24-7664-3035, Rev. A

Issued November 25, 2015

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Penn A421ABD Series Specifications

General

Brand	Penn
Model	A421ABD Series
Category	Controller
Language	English

Summary

Mounting Guidelines

General Mounting & DIN Rail

Observe the following guidelines when locating and mounting an A421 control: ... To mount a Type 1/IP20 control on DIN rail:

Wiring Safety & Best Practices

Electrical Shock Hazard Warning

WARNING: Risk of Electric Shock.

Conductor & Rating Compliance

IMPORTANT: Use copper conductors only. ... IMPORTANT: Do not exceed the A421 control's electrical ratings.

IMPORTANT: When connecting an A99 sensor with a shielded cable to an A421 Control, connect the cable shield drain lead to the COM (common) terminal on the sensor and binary input terminal block (TB3).

Wiring Diagram & Terminals

Common Power Source Wiring

Figure 4: Wiring the A421 Series Controls Using the Same Power Source to Power the Control Operation and Power the Controlled Equipment

Control Interface & Setup

Parameter Codes Overview

Parameter Codes and Modes of Operation

Parameter Settings Explained

Relay Off Temperature (OFF): Select the temperature at which the output relay de-energizes... Relay On Temperature (On): Select the temperature at which the output relay energizes...

Operation Mode & Settings

Mode Logic & Delay Settings

The heating or cooling mode is determined by the On and OFF value relationship as follows: ... Anti-Short Cycle Delay (ASd): Select the minimum time that the output relay remains off...

Sensor Failure & Temperature Units

Sensor Failure Mode (SF): Select how the control's output relay operates... Temperature Units (Un): Select the desired temperature scale...

Restricted Adjustment Limits

LtS, HtS, & tSb Functions

Low Temperature Stop (LtS): Select the lowest temperature value... High Temperature Stop (HtS): Select the highest temperature value... Temperature Setback (tSb): Select a temperature value for setting back the On and OFF temperature values.

Parameter Setup Details

Defrost & Binary Input Parameters

Defrost Cycle Time (dFt): Select the time (in minutes)... Defrost Interval (dl): Select the time (in hours)... Binary Input Modes (bln): The BIN mode allows you to select how the A421 control operates...

Setup Menu Navigation

Menu Structure & Navigation

The A421 temperature controls provide a Basic and an Advanced setup menu... Menu Navigation Guidelines ... The parameter code flashes on and off.

Basic Menu Access & Operation

Advanced Menu Navigation

Accessing & Operating Advanced Menu

Defrost Cycle Setup & Control

Regular/Timed Defrost Setup

Manual Defrost Control Procedures

Defrost Control Behavior Scenarios

Automatically Enabled Defrost Control

SdF & Binary Input for Defrost

User Adjustment Restriction

Restriction Options & Enabling

You can restrict user adjustment of the A421 control... You set the A421 control into the restricted adjustment mode by positioning the P1 jumper...

Restricted Adjustment Behavior Diagram

Restricted Adjustment Setup

Setup Steps for Restricted Mode

To set up the restricted adjustment feature:

Adjusting Control in Restricted Mode

OFF Value Adjustment Procedure

To adjust the OFF value (and shift the On/OFF control band) within the restricted adjustment range, when the control is in the restricted adjustment mode: