1
1.0 Introduction
The Walchem WDIS Series controllers are wall mount disinfection controllers that provide two relays
used to perform on/off control of chlorine, chlorine dioxide, ozone or Peracetic acid. Two additional
relays are available for use as alarms or probe washing. A fifth output is used as a diagnostic alarm.
An isolated 4-20 mA output is optional.
They are only compatible with Walchem sensors. The choice of the type of sensor is selected through
the keypad. The sensors are temperature compensated internally; no temperature signal is transmitted
to the controller. The controller will prompt you to calibrate the sensor at the desired frequency.
2.0 Specifications
2.1
Measurement Performance (Sensors)
Chlorine Dioxide
Peracetic
Acid Ozone
Chlorine
Range
0-10 mg/l
0-1000 mg/l
0-10 mg/l
0-10 mg/l
Resolution
0.01 mg/l
1 mg/l
0.01 mg/l
0.01 mg/l
Cross Sensitivity Free Chlorine (5%),
Ozone
Free
Chlorine
(5%)
Bromine, Ozone, Iodine,
ClO2, Di-/Trichloramine, or
Bromamine
Flow Rate of Sample
30 to 100 liters/hour (0.13 to 0.44 gallons/minute)
pH Range of Sample
1.0 – 14.0
6.8 – 8.0 (7.2 to 7.4 ideal)
Conductivity Range of Sample
50 to 10,000
μ
S/cm
Up to 4% NaCl
Response Time
30 sec
3 min
30 sec
30 sec
Electrical
Power Requirements
± 5 VDC, 5 mA maximum
Signal
0 to -1000 mVDC
Maximum Cable Length
1000 ft (305 m)
Cable Required
2 twisted pair, 22 AWG, shielded, 35 pF/ft (Walchem 100084 or Belden 8723)
Mechanical
Operating Temperature
0 to 50°C (41 to 122°F)
0 to 45°C (41 to 113° F)
Operating Pressure
0 to 1 atm (0 to 14.7 psi)
Storage Temperature
0 to 50°C (41 to 122°F)
Shelf Life
1 year
Flow Cell Inlet
¼” NPTF
Flow Cell Outlet
¾” NPTF
Wetted Materials of Construction
Sensor Body
PVC, Polycarbonate
Membrane
Silicone
PTFE
Flow Cell Body
Isoplast
O-Ring
FKM
