3
Issue 1.0
Installation
1.
The unit is designed to be mounted in any single-gang British Standard pattress box (surface or flush
mounted) which has a minimum internal depth of 20mm.
2. Ensure best-practices are used when choosing a location for the thermostat so that optimal thermostatic
control is achieved. Do not mount near drafts, heaters, radiators, air conditioners, in direct sunlight or
any other place where the sensed temperature may be unnaturally influenced. A good mounting height
is typically between 1m and 2m from the floor.
3.
Connect the wiring as shown in Figure 1 (or any suitably appropriate form) via the screw-terminals.
Make sure to choose the correct output terminals that are suitable to your application.
4. Adjust the internal thumbwheels to suit the desired operational requirements (see below).
5.
Affix the thermostat to the pattress box using the supplied M3.5 raised-countersunk screws then finally
insert the screw-caps for a neat finish.
6.
The screw caps may be removed without damage using a sticky putty such as blu-tack.
Operation
1.
Adjust the setpoint (“Setpoint”) dial to the temperature the room is to be regulated to in the ‘Med’ mode
(typically 20ºC).
2.
Adjust the set-back/set-forward (“S’Bck/S’Fwd”) dial to the number of °C either side of the ‘Med’
temperature that the ‘Low’ and ‘High’ temperatures are to be (typically 2°C).
3.
Set the differential (“Diff.”) to the total temperature swing either side of the resulting setpoint that the
room temperature is required to keep within (typically 1°C).
4. Example set-up:
Setpoint set to 20ºC, Differential set to 1ºC, Set-Back/Set-Forward set to 2°C.
Low mode - The unit will maintain the temperature between 17.5ºC and 18.5ºC
Med mode - The unit will maintain the temperature between 19.5ºC and 20.5ºC
High mode - The unit will maintain the temperature between 21.5ºC and 22.5ºC
Technical Specification
Power supply:
220V - 240V AC 50Hz (live/neutral)
22V - 26V AC or DC [/24V variant only]
Output switch rating:
10A, 250V AC 50Hz (resistive)
Output switch type:
Changeover relay (volt-free)
Temperature control:
[Med setpoint]: +12°C to +26°C
[Low/High setpoint]: 0°C to 7°C below/above the Med
setpoint
Temperature differential:
0.25°C to 4°C
Sensor drift:
0.15°C over 5 years
Guarantee:
5 Years
Weight:
90g
Dimensions mm:
86mm x 86mm x 27mm
Product Accessories
MSD-154
M3.5 tamperproof screws
MSD-155
Tamperproof screwdriver for MSD-154 screws
Ensure the electrical supply is isolated before making any connections or adjustments.
!
Ensure the electrical supply is isolated before making any connections or adjustments.
!
Notes
1.
Applying power for the first time
: The output of the thermostat may not switch in response to temperature for
up to 60 seconds after first powering on. This is normal behaviour due to a necessary initialisation phase - please
wait until this is completed before attempting to test the thermostat. Normal operation will resume as soon as the
initialisation phase has completed.
If the unit has already completed initialisation then short interruptions of power of up to 5 minutes will not trigger the
initalisation phase and the humidistat will resume normal operation immediately within a couple of seconds. Power
interruptions longer than 5 minutes may trigger the initialisation phase again.
