CPT Current Position Transmitter
Installation Operation& Maintenance Manual
Doc No. : HumG-CPT-20 Rev0 Page 3 / 6 Valve Automation Leader, HKC
1. Introduction
1.1. Purpose
The purpose of this manual is to introduce and explain the installation, operation and maintenance of
CPT (Current Position Transmitter) for electric actuators. Before you start work, please read this manual
carefully and this manual contains important information regarding the installation, operation,
maintenance for HQ series electric quarter turn actuator. This manual can be changed without notice for
quality improvement.
1.2. Safety Notices
Safety notices in this manual outline precaution the user must take to reduce the risk of personal injury
and damage to the equipment. The user(s) must read these instructions before the installation, operation
or maintenance of HQ-series electric actuators.
DANGER:
Refers to personal safety and alerts the user to danger or harm.
The hazard or unsafe practice will result in severe injury or death.
WARNING:
Refers to personal safety. Alerts the user to potential danger.
Failure to follow warning notices could result in personal injury or death.
CAUTION:
Directs the user’s attention to general precautions that, if not followed, could
result in personal injury and/or equipment damage
.
Notes: Highlighted information is critical to the user’s understanding of the actuator’s
installation and operation.
2. Pre-check points before operation
2.1. Check point
2.1.1. User should confirm if actuator and valve are assembled correctly and firmly.
2.1.2. And check limit switches, stopper bolts, indicator setting.
2.1.3. Please check electric power, input and output signal, and wiring and etc.
2.1.4. In case electric power is 3 phases, you must check Rotating direction of actuator.
2.1.5. How to check rotating direction
① Place actuator at the position 50% by manual first, and supply electric power for about 5 seconds
toward “Close” from panel.
② Then, you will understand actuator is operating in correct or opposite direction. If it turns to
“Open” direction, cut the power, and change two wires of the three of 3 phases.
3. General concept
3.1. General information
As a potentiometer reads actuator’s current position and transfers resistance value to CPT card.
And it indicates actuator position throughout the stroke by 4~20 mA output signal.
3.2. Standard specification
Position conversion accuracy
It could be different based on installation and/or operation
condition.
minute (input and output power to ground)
Frequency : 0.2~34 Hz, within 30 minutes
4. Main function and how to use Zero / Span setting
