Penn A421 Series Installation Manual

Applications
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 with
Power Cords are single-stage, electronic temperature
controls with a single-pole, double-throw (SPDT) output
relay and 120 VAC power cords factory wired to the
control.
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 and off status.
A421 Control models 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).
A421 Control models with Type 1, IP20 enclosures are
available with a single power cord and a combination
(piggyback) 120 VAC, grounded plug and outlet; or with
dual power cords consisting of a 120 VAC grounded plug
on a 6 ft cord and 120 VAC grounded outlet on a 6 ft cord.
A421 Control models with Type 4X, IP66 enclosures are
available with a single power cord and a combination
(piggyback) 120 VAC, grounded plug and outlet.
A421 Series Standard Electronic Temperature
Controls with Power Cords Installation Guide
See Ordering information
accessories.
Dimensions
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)
Parts included
Each A421 Control includes a Johnson Controls
PENN A99 Series temperature sensor. See
®
Temperature Sensors, Wiring, and
for more information about A99 sensors.
A99 Series Temperature Sensors
The A421 Controls require an A99 sensor, and each A421
Control includes an A99 sensor. Any A99 Series sensor
Part No. 24-7664-3027 Rev. D
2019-01-24
for more model information and
or
®
A99 Series
Technical specifications
A421ABG, A421ABJ, A421AEJ,
A421AEJ