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.
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 you can 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°F to 212°F or -40°C 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).