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Hi Lauren,

The below parts have just arrived! That was very quick and efficient!

Thankyou for organising that


Hi Dave,

One happy customer, thanks for the assistance with this.


You’re the best, thanks!

Have a nice weekend.

Best regards / Met vriendelijke groet


Thanks Charlotte.

I wish all suppliers where as efficient and quick as you guys.

Best Regards,

Peter Jackson

Hi Emma

Many thanks for your quick response. Just discovered your website today but it looks excellent!

Nicola Allan


Installed these today, worked a treat.




dziękuję za doskonałą obsługę

systemu przeciwpozarowego i za wspaniale wsparcie.


Good afternoon Lauren.

Thank you for the fast response.

As ever I am very impressed with the excellent service you offer.


Good Morning Emma,

I must say you are the best.  Normally I do not receive such fast replies from overseas suppliers, and that too complete with courier charges.

Have a nice day.



Good morning Emma,

Order has been well received yesterday, I can say that we are very happy with your service.

Best regards,



Thank you all for your support on this project. We’ve worked well together in my opinion and would hope that we can do so again in the future.



Please pass on my thanks to Lauren for sorting out my order yesterday, top class service yet again from your team.


Dear Sales,

Equipment arrived on the vessel at berth as arranged, thank you so much for your assistance.

Jaqueline Bernard

Ms Deborah

We are extremely grateful and appreciative of yours and your team’s customer oriented attitude and behavior.

We look forward to further business dealings with your organization.


Cheers Dave you're a star

Kind Regards



Thanks for all your help and excellent customer service! :-)

Kind Regards,

Ainsley Cooper

Dear Hannah,

After several weeks of trying to find these parts; you located part numbers, cost, availability and air freight within one day!

Nancy Johnson

We have just purchased a SOLO kit from yourselves and I have say we have been very impressed with the service and support provided – thank you 


Thanks Lauren,

it’s so nice to deal with a company who are so accommodating, it’s been a refreshing change for us!


Dear Charlotte,

I just wanted to say thank you for the utter super swift service that I received from Acorn Fire & Security regarding my recent order.

Well done and regards,

Ian Stone

We enjoy one of the best supplier relationships with Acorn due to the professionalism & quick response times allied with an enjoyable friendly nature of all the staff.


Hi Dave,

Many thanks for your swift reply & valued advise. (great service)



Thanks a lot,  we really appreciate professional work and good service.

We also wish you a Merry Christmas and Happy new year!


Hello Aleks and Dave

Many thanks firstly for the quick response.

Once again many thanks for such a great turnaround.

Dave Lewis

Thankyou so much for your assistance, I don't know how you managed to source this equipment, but I'm very glad you did. All fitted and working now!!

Med vennlig hilsen

K Larsen

Hi Dave,

The service and support from Emma and the other staff has been superb and as a new customer purchasing wise I will now be placing all orders with Acorn.

Andrew Sullivan

Many thanks as always for the quality and speed of the service!


Dear Sirs,

Just a line to thank you for the prompt delivery of my JSB terminators which arrived at 09:00 today.


Stuart Willcock


Perfect service, thank you



Hi Hannah,

Thank you very much for the quick turnaround, as this was a big ask in a short space of time. Please convey my appreciation to all involved.

Steve Sneddon

Hi Emma,

Thank you for your awesome work!

William J

Dear Lauren,
Thank you so much and very glad to be your customer.
Juladit C.

Juladit C

Hi Deborah

Thank you very much for going extra mile for me. Great!

Best Regards


Thanks to Lauren for helping resolve a problem.

She was helpful, efficient, and above all pleasant.

A real asset.


To all at Acorn,

On behalf of myself, and our Service staff, thankyou for your continued support, and thankyou for going the extra mile last week; our Client is now extremely satisfied!


Dear Lauren, very good and prompt services, thanks!

Wishing you have a Merry Christmas and a Happy New Year 2015!



Many thanks to you and Aleks it is a great help.



Hi Dave

Just a quick note to say thanks for the advice on the replacement of the Mother board. We attended a week ago and all went smoothly, no problems since (touch wood!).


Hello again,

Equipment arrived on MT as arranged.......amazing.

Marios Georgiades


Just a quick mail to say what a brilliant service your team offer.

I purchased some sounders a few months back and only just got round to installing them.

Unfortunately one of the bases was missing which we didn't realise until installation day.

I dropped an enquiry via your website at the beginning of the week and to my delight, the base arrived this morning free of charge.

Once again thank you.



Again many thanks for your help and assistance.

System now fully back on line.

Andrew Kelly

Acorn Fire & Security have vastly improved our business, through excellent customer service from point of order, through to rapid delivery to our Engineers in the field.

Steven Troy

I received and checked through my order today and everything is as it should be.

Thanks again to you and to Acorn fire and security for a great and efficient service.


Thank you for the support and service you provide. I look forward to working with you guys again in the new year!


Thanks Lauren

I wish all suppliers got back to me as quickly as you do!

Dani Webster


Thanks for all your help with this last night we appreciate the service you provided to us.

Kind Regards


Hi Lauren,

Thank you very much, excellent service as usual.



Dear Hannah,

The test equipment arrived one day early, received on Tuesday; wunderbar!

Jürgen Schulz

Hi Emma,

Thank you very much for all your help - excellent service!

Fiona McGregor


Ashley you're like a salesman dream!!

Thanks for your help Ash.

Kindest regards,


Hochiki MTL 7787+ Zener Barrier

Hochiki MTL 7787+ Zener Barrier


Product Code: MTL7787

Please Contact Us for Price & Availability.

Contact Us

Hochiki MTL 7787+ Zener Barrier 

Model MTL7787+ is an intrinsically safe, zone-powered, Zener-diode barrier for use in conventional fire detection systems for protection within hazardous areas. Model MTL7787+ is certified 'ia' for all zones and 'IIC' for all explosive atmospheres.


  • Simple installation onto standard DIN railing
  • Removable colour-coded terminals for easy connection
  • Accommodates conductors up to 2.5 sq mm
  • Supports up to two zones of I.S. products
  • Enclosure (box) available - DX070
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