Page 1
CM31 & CM37
FEATURES
• • Battery powered by 2 AA size (LR6) alkaline cells
ANALOGUE CHRONOTHERMS
PRODUCT SPECIFICATION SHEET
The CM31 and CM37 chronotherms
are designed to provide automatic time
and temperature control of heating
systems in the home.
CM31 is a simple to use battery
powered analogue clock-thermostat
with electronic temperature control and
24 hour programming capability.
CM37 has the same features as CM31
but with the addition of a 7 day clock
programme.
Both products meet the requirements
of CE.
• • Attractive modern styling
• • Easy to use programming controls
• • Quartz crystal clock with 12 hour clock face, hour and
minute hands
• • CM31 has 24 hour programme with 96 programming
tappets (15 minute steps)
• • CM37 has 7 day programme with 168 programming
tappets (1 hour steps)
• • P+I temperature control
• • ±± 0.5°C control differential
• • Two temperature levels (Comfort and Economy)
• • Comfort temperature range 10 to 30°C
• • Economy temperature range 5 to 25°C
• • Choice of operating modes : Automatic / Comfort /
Economy
• • Battery life 1 year (nominal)
• • 24...240 V SPDT potential free contacts for wide
flexibility of application
• • Normally-closed (nc) contact terminal protected by
break-off tab to guide installer in 2 wire applications
• • 8 A resistive, 3 A inductive switch rating
• • Batteries supplied
• • Replaceable clock module
− − 24 hour clock, part number R42009899-001
− − 7 day clock, part number R42009899-002
EN0R 8502 R1
Page 2
CM31 & CM37 CHRONOTHERMS
DIMENSIONS
SPECIFICATIONS
:
:
ORDERING SPECIFICATION
Product
Power supply : 2 x 1.5 V IEC LR6 (AA) Alkaline batteries
Battery life : 12 months minimum
Switch type : SPDT (potential free) latching relay
Switch rating : 24...230 V~, 50...60 Hz, 8 A resistive;
Time switch : Quartz crystal clock
Clock accuracy : 1 minute 30 seconds per year
Programme : CM31 has 96 tappets (15 minute
Operating
modes
Temperature
setting
CM31 is a 24-hour analogue clock
thermostat
CM37 is a 7-day analogue clock
thermostat
3 A inductive @ 0.6 pf
100,000 operations
12 hour clock face
24-hour programme for CM31
7-day programme for CM37
Clockwise setting only
clock drift ±1 second /day @ 25°C
intervals) Minimum programme interval
15 minutes (1 tappet)
: CM37 has 168 tappets (1 hour intervals)
Minimum programme interval 2 hours (2
tappets)
: Automatic
Manual (Comfort/Economy)
setting by slider
: Comfort setpoint 10 to 30°C
Economy setpoint 5 to 25°C
setting by rotary knob
Temperature
control
Control form : ON/OFF
Control
differential
Comfort setpoint
accuracy
Minimum
ON/OFF period
Wiring : up to 2 x 0.75 to 2.5 mm2 wiring
Dimensions : 135 x 90 x 29 mm (w x h x d)
Environmental : Operating temperature range 0 to 40°C
Protection class : IP30
Approvals : Meets the requirements of CE.
P+I electronic control, with fixed cycle
rate of 6 cycles/hour (nominal)
: ±0.5 °C @ 3 °C /hour, at 20°C, 50%
load, 8 A
: ±1.0°C
: 2 minutes
connections
135 x 178 x 29 mm (w x h x d) (flap
open)
Shipping and storage temperature range
-20 to 55°C
Humidity range 0 to 90% rh, noncondensing
Relevant standards EN60730-1 (1995),
EN55014-1 (1997), EN55014-2 (1996).
T6631B1005 - CM31 with 24 hour clock programme
T6637B1009 - CM37 with 7 day clock programme
EN0R 8502 R1 2
Page 3
CM31 & CM37 CHRONOTHERMS
INSTALLATION
Valve actuator control
WIRING
Direct burner control
LOCATION
The CM31 or CM37 Chronotherm is the temperature control
element in the heating system and MUST be located in a
position with good air circulation at average room
temperature on an inside wall 1.5 metres above the floor
level. Do not position the Chronotherm near sources of heat
(radiators, hot air vents, TV or lights), near doors or windows,
or in direct sunlight.
MOUNTING
CM31 and CM37 can be mounted directly on the wall surface
or on an electrical wallbox. Mounting screws are supplied for
both alternatives.
WIRING
CM31 and CM37 are designed for fixed wiring only and must
be installed in accordance with latest l.E.E. regulations.
Ensure the wiring connections to the supply are via a fuse
rated at 8 amps (max) and a Class "A" switch (having contact
separation of at least 3 mm in all poles).
CM31/
CM37
IMPORTANT
Combi boiler control
1. The installer must be a trained service engineer
2. Disconnect the power supply before beginning
installation
CM31/
CM37
CM31/
CM37
COMBI BOILER
3 EN0R 8502 R1
Page 4
CM31 & CM37 CHRONOTHERMS
Electric heating control
Zone valve control (i)
CM31/
CM37
Electric Heating Systems
Systems rated above 8 A resistive
(1.75 kW) should be controlled via a
contactor.
Systems rated below 8 A can be
switched directly by the CM31 or CM37
relay.
It is recommended that a voltage
dependent resistor rated at 275 V
r.m.s., 23 joules, 775 V clamping
voltage (e.g. Philips V275LA2) is
installed across the contactor coil to
suppress interference from voltage
spikes.
Zone valve control (ii)
CM31/
CM37
CM31/
CM37
1.5kW HEATER
Zone valve control (iii)
CM31/
CM37
20 Amp
contactor
CM31/
CM37
4.0 kW HEATER
Honeywell Control Systems Limited http://europe.hbc.honeywell.com
Newhouse Industrial Estate
Motherwell ML1 5SB
United Kingdom
EN0R 8502 R1
Loading...