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.
Dimensions
Figure 1: A421 Control with Type 1 (NEMA), IP20
enclosure dimensions, in. (mm)
A421 Series Standard Electronic Temperature
Controls Installation Guide
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. Refer to
®
Temperature Sensors documentation for details.
A99 Series Temperature Sensors
The A421 Controls require an A99 sensor, and each A421
Control includes an A99 sensor. Any A99 Series sensor
works with the A421 Series Controls. Do not replace an
A99 Series sensor with any other brand, series, or type
of temperature sensor. See
available A99 Series sensor models.
You can extend the sensor leads in the field. See Table
1 for information about wire sizes and lengths. On
long sensor cable runs, use shielded cable to reduce
electromagnetic interference (EMI). Observe EMI best
practices when you route sensor leads.
Do not completely immerse the A99 Series sensors in
water or any other liquid. The A99 sensors are moisture
tolerant and splash resistant but if you immerse the
sensor, liquid can enter the sensor probe where the steel
tube meets the wire cable and result in sensor failure,
which voids any warranty.
Part No. 24-7664-3019 Rev. E
2019-10-14
or
®
A99 Series
Ordering information for
A421ABC, A421AEC, A421GBF,
A421GEF