1. INTRODUCTION AND GENERAL DESCRIPTION
The Yokogawa EXAxt PH450G is a converter designed for industrial process monitoring, measurement and control applications. This instruction manual contains the information needed to install, set up, operate and maintain the unit correctly.
This manual also includes a basic troubleshooting guide to answer typical user questions.
Yokogawa can not be responsible for the performance of the EXAxt converter if these instructions are not followed.
1-1. Instrument check Upon delivery, unpack the instrument carefully and inspect it to ensure that it was not
damaged during shipment. If damage is found, retain the original packing materials (including the outer box) and then immediately notify the carrier and the relevant Yokogawa sales office.
Make sure the model number on the nameplate affixed to the side of the instrument agrees with your order. Example of the nameplate is shown below.
The EXAxt converter is intended to be used for continuous on-line measurement of pH and/or Redox in industrial installations. The unit combines simple operation and microprocessor-based performance with advanced self-diagnostics and enhanced communications capability to meet the most advanced requirements.
The measurement can be used as part of an automated process control system. It can also be used to indicate operating limits of a process, to monitor product quality, or to function as a controller for a dosing/neutralisation system.
Sensors should normally be mounted close to the converter in order to ensure easy calibration and peak performance. If the unit must be mounted remotely from the sensors, WF10 extension cable can be used, up to a maximum of 60 meters (150 feet), with a BA10 junction box, and up 10 meters standard sensor cable.
The EXAxt is delivered with a general purpose default setting for programmable items (see Chapter 5). While this initial configuration allows easy start-up, the configuration should be adjusted to suit each particular application.
An example of an adjustable item is the type of temperature sensor used. The EXAxt can be adjusted for a number of different types of temperature sensors.
Details provided in this instruction manual are sufficient to operate the EXAxt with all Yokogawa sensor systems and a wide range of third-party commercially available probes.
For best results, read this manual in conjunction with the corresponding sensor instruction manual.
Yokogawa designed the EXAxt converter to withstand industrial environments. It meets all the CE regulatory standards. The unit meets or exceeds stringent requirements (see section 2) without compromise, to assure the user of continued accurate performance in even the most demanding industrial installations.
2. GENERAL SPECIFICATIONS OF EXAXT PH450G
(A) Inputs specs : Dual high impedance input (≥ 1012Ω)
(under referance conditions)
(B) Input ranges
pH : -2 to 16 pH
ORP : -1500 to 1500 mV
rH : 0 to 100 rH
– Pt1000 : -30 to 140ºC
– Pt100 : -30 to 140ºC
– 350Ω (DKK) : -30 to 140ºC
– 5k1 : -30 to 140ºC
– 6k8 : -30 to 140ºC
– PTC10k : -30 to 140ºC
– NTC 8k55 : -10 to 120ºC
– 3kBalco : -30 to 140ºC
pH input : ≤ 0.01 pH
ORP input : ≤ 1 mV
Temperature : ≤ 0.3 ºC (≤ 0.4 ºC for Pt100)
Step response : < 4 sec for 90% (pH 7 – pH 4)
Note on performance specifications
The following tolerance is added to above performance.
mA output tolerance: ±0.02 mA of “4-20 mA“
(D) Transmission signals
General : Two isolated outputs of 4-20 mA. DC with common negative. Maximum load 600Ω. Bi-directional HART® digital communication, superimposed
on mA1 (4-20 mA) signal
Output functions : Linear or Non linear (21-step table) output for pH, temperature, ORP or rH
Control function : PID control
Burnout function : Burn up (21.0 mA) or burn down (3.6 mA) to signal failure acc.
Adjustable damping. Expire time
Hold : The mA-outputs are frozen to the last/fixed value during calibration/
(E) Contact outputs
General : Four SPDT relay contacts with display indicators
Switch capacity : Maximum values 100 VA, 250 VAC, 5 Amps.(*)
Maximum values 50 Watts, 250 VDC, 5 Amps.(*)
Status : High/Low process alarms, selected from pH, ORP, rH and temperature
Configurable delay time and hysteresis
Control function : On/Off, PID duty cycle or pulsed frequency control
Wash : Contact can be used to start manual- or interval time wash cycles
Hold : Contact can be used to signal the Hold situation.
Fail : Contact S4 is programmed as fail-safe contact
(*) Note: When contact output current is more than 4 Amps. ambient temperature should be
less than 40ºC.
(F) Contact input : Remote wash cycle start.
(G) Temperature compensation
Function : Automatic or manual
Compensation to Nernst equation
Process compensation by configurable temperature coefficient,
NEN6411 for water or strong acids/bases or programmable matrix
(H) Calibration : Semi-automatic 1 or 2 point calibration using pre-configured NIST, US, DIN buffer tables 4, 7 & 9, or with user defined buffer tables, with automatic stability check
Manual adjustment to grab sample
(I) Logbook : Software record of important events and diagnostic data readily available in the display or through HART®.
(J) Display : Graphical Quarter VGA (320 x 240 pixels) LCD with LED backlight and touchscreen. Plain language messages in English, German, French, Spanish, Italian, Swedish ,Portuguese and Japanese.
(K) Shipping details
Package size : 290 x 300 x 290 mm (L x W x D) (11.5 x 11.8 x 11.5 inch)
Package weight : app. 2.5 kg (5.5 lbs)
Converter weight : app. 1.5 kg
L) Housing : Cast aluminum housing with chemically resistant coating;
Polycarbonate cover with Polycarbonate flexible window : Protection IP66 / NEMA 4X / CSA Type 3S
Colour : Silver grey
PH450G-A(D)-A : IP66 cable glands are supplied with the unit
PH450G-A(D)-U : NEMA 4X close up plugs are mounted in the unused cable entry holes and can be replaced by conduit fittings as required Pipe, Panel or Wall mounting using optional hardware Optional conduit adapter
G1/2, 1/2NPT or M20 female
(M) Power supply
PH450G-A : Ratings; 100-240 V AC Acceptable range; 90 to 264 V AC
Ratings; 50/60 Hz Acceptable range; 50 Hz ±5%, 60 Hz ±5%
Power Consumption; 15 VA
PH450G-D : Ratings; 12-24 V DC Acceptable range; 10.8 to 26.4 V DC
Power Consumption; 10 W
N) Safety and EMC conforming standards ,
Safety : EN 61010-1
CSA C22.2 No.61010-1
FM3611 Class I, Div.2, Group ABCD,T6 for Ta -20 to 55ºC
EMC : EN 61326-1 Class A, Table 2 (For use in industrial locations)
EN 61000-3-2 Class A
Korea Electromagnetic Conformity Standard
Installation altitude: 2000 m or less
Category based on IEC 61010: II (Note)
Pollution degree based on IEC 61010: 2 (Note)
Note: Installation category, called over-voltage category, specifies impulse withstand voltage.
Category II is for electrical equipment.
Pollution degree indicates the degree of existence of solid, liquid, gas or other inclusions which may reduce dielectric strength. Degree 2 is the normal indoor environment.